Entry Changes (#364)

* Initial refactor: Allow EntryMapping to have null targetName, add EntryChange in favor of entry changing methods in GuiController

* Fix resetting name not actually removing it, and renaming a class causing name collisions with itself

Closes #246.

* Use name proposer for setting default deobf name

Closes #314

* Make network protocol use EntryChange directly

* Handle writing other data correctly when the deobf name is null

* b

* Add some new abstraction stuff

* Use pattern matching instanceof

* Move classes out of newabstraction package

* Make EntryChange final

* Regenerate equals and hashCode

* Convert EntryMapping to record

* Make TristateChange final

* Safety guard null accessModifier initialization

53 files changed, 872 insertions, 1000 deletions

diff --git a/enigma-server/docs/protocol.md b/enigma-server/docs/protocol.md
index c14ecb81..83ef4c01 100644
--- a/enigma-server/docs/protocol.md
+++ b/enigma-server/docs/protocol.md
@@ -75,21 +75,15 @@ struct Packet {
 The IDs for client-to-server packets are as follows:
 - 0: `Login`
 - 1: `ConfirmChange`
-- 2: `Rename`
-- 3: `RemoveMapping`
-- 4: `ChangeDocs`
-- 5: `MarkDeobfuscated`
 - 6: `Message`
+- 7: `EntryChange`
 
 The IDs for server-to-client packets are as follows:
 - 0: `Kick`
 - 1: `SyncMappings`
-- 2: `Rename`
-- 3: `RemoveMapping`
-- 4: `ChangeDocs`
-- 5: `MarkDeobfuscated`
 - 6: `Message`
 - 7: `UserList`
+- 8: `EntryChange`
 
 ### The utf struct
 ```c
@@ -196,6 +190,45 @@ struct Message {
 - `entry`: The entry that was modified.
 - `new_name`: The new name for the entry.
 
+### The entry_change struct
+```c
+typedef enum tristate_change {
+    TRISTATE_CHANGE_UNCHANGED = 0,
+    TRISTATE_CHANGE_RESET = 1,
+    TRISTATE_CHANGE_SET = 2
+} tristate_change_t;
+
+typedef enum access_modifier {
+    ACCESS_MODIFIER_UNCHANGED = 0,
+    ACCESS_MODIFIER_PUBLIC = 1,
+    ACCESS_MODIFIER_PROTECTED = 2,
+    ACCESS_MODIFIER_PRIVATE = 3
+} access_modifier_t;
+
+// Contains 4 packed values:
+// bitmask   type
+// 00000011  tristate_change_t deobf_name_change;
+// 00001100  tristate_change_t access_change;
+// 00110000  tristate_change_t javadoc_change;
+// 11000000  access_modifier_t access_modifiers;
+typedef uint8_t entry_change_flags;
+
+struct entry_change {
+    Entry entry;
+    entry_change_flags flags;
+    if <deobf_name_change == TRISTATE_CHANGE_SET> {
+        utf deobf_name;
+    }
+    if <javadoc_change == TRISTATE_CHANGE_SET> {
+        utf javadoc;
+    }
+}
+```
+- `entry`: The entry this change gets applied to.
+- `flags`: See definition of `entry_change_flags`.
+- `deobf_name`: The new deobfuscated name, if deobf_name_change == TRISTATE_CHANGE_SET
+- `javadoc`: The new javadoc, if javadoc_change == TRISTATE_CHANGE_SET
+- `access_modifiers`: The new access modifier, if access_change == TRISTATE_CHANGE_SET (otherwise 0)
 
 ### Login (client-to-server)
 ```c
@@ -223,44 +256,6 @@ struct ConfirmChangeC2SPacket {
 ```
 - `sync_id`: the sync ID to confirm.
 
-### Rename (client-to-server)
-```c
-struct RenameC2SPacket {
-    Entry obf_entry;
-    utf new_name;
-    boolean refresh_class_tree;
-}
-```
-- `obf_entry`: the obfuscated name and descriptor of the entry to rename.
-- `new_name`: what to rename the entry to.
-- `refresh_class_tree`: whether the class tree on the sidebar of Enigma needs refreshing as a result of this change.
-
-### RemoveMapping (client-to-server)
-```c
-struct RemoveMappingC2SPacket {
-    Entry obf_entry;
-}
-```
-- `obf_entry`: the obfuscated name and descriptor of the entry to remove the mapping for.
-
-### ChangeDocs (client-to-server)
-```c
-struct ChangeDocsC2SPacket {
-    Entry obf_entry;
-    utf new_docs;
-}
-```
-- `obf_entry`: the obfuscated name and descriptor of the entry to change the documentation for.
-- `new_docs`: the new documentation for this entry, or an empty string to remove the documentation.
-
-### MarkDeobfuscated (client-to-server)
-```c
-struct MarkDeobfuscatedC2SPacket {
-    Entry obf_entry;
-}
-```
-- `obf_entry`: the obfuscated name and descriptor of the entry to mark as deobfuscated.
-
 ### Message (client-to-server)
 ```c
 struct MessageC2SPacket {
@@ -269,6 +264,14 @@ struct MessageC2SPacket {
 ```
 - `message`: The text message the user sent.
 
+### EntryChange (client-to-server)
+```c
+struct EntryChangeC2SPacket {
+    entry_change change;
+}
+```
+- `change`: The change to apply.
+
 ### Kick (server-to-client)
 ```c
 struct KickS2CPacket {
@@ -286,13 +289,8 @@ struct SyncMappingsS2CPacket {
 struct MappingNode {
     NoParentEntry obf_entry;
     boolean is_named;
-    if<is_named> {
-        utf name;
-        boolean has_javadoc;
-        if<has_javadoc> {
-            utf javadoc;
-        }
-    }
+    utf name;
+    utf javadoc;
     unsigned short children_count;
     MappingNode children[children_count];
 }
@@ -300,56 +298,10 @@ typedef { Entry but without the has_parent or parent fields } NoParentEntry;
 ```
 - `roots`: The root mapping nodes, containing all the entries without parents.
 - `obf_entry`: The value of a node, containing the obfuscated name and descriptor of the entry.
-- `name`: The deobfuscated name of the entry, if it has a mapping.
-- `javadoc`: The documentation for the entry, if it is named and has documentation.
+- `name`: The deobfuscated name of the entry, if it exists, otherwise the empty string.
+- `javadoc`: The documentation for the entry, if it exists, otherwise the empty string.
 - `children`: The children of this node
 
-### Rename (server-to-client)
-```c
-struct RenameS2CPacket {
-    unsigned short sync_id;
-    Entry obf_entry;
-    utf new_name;
-    boolean refresh_class_tree;
-}
-```
-- `sync_id`: the sync ID of the change for locking purposes.
-- `obf_entry`: the obfuscated name and descriptor of the entry to rename.
-- `new_name`: what to rename the entry to.
-- `refresh_class_tree`: whether the class tree on the sidebar of Enigma needs refreshing as a result of this change.
-
-### RemoveMapping (server-to-client)
-```c
-struct RemoveMappingS2CPacket {
-    unsigned short sync_id;
-    Entry obf_entry;
-}
-```
-- `sync_id`: the sync ID of the change for locking purposes.
-- `obf_entry`: the obfuscated name and descriptor of the entry to remove the mapping for.
-
-### ChangeDocs (server-to-client)
-```c
-struct ChangeDocsS2CPacket {
-    unsigned short sync_id;
-    Entry obf_entry;
-    utf new_docs;
-}
-```
-- `sync_id`: the sync ID of the change for locking purposes.
-- `obf_entry`: the obfuscated name and descriptor of the entry to change the documentation for.
-- `new_docs`: the new documentation for this entry, or an empty string to remove the documentation.
-
-### MarkDeobfuscated (server-to-client)
-```c
-struct MarkDeobfuscatedS2CPacket {
-    unsigned short sync_id;
-    Entry obf_entry;
-}
-```
-- `sync_id`: the sync ID of the change for locking purposes.
-- `obf_entry`: the obfuscated name and descriptor of the entry to mark as deobfuscated.
-
 ### Message (server-to-client)
 ```c
 struct MessageS2CPacket {
@@ -364,3 +316,13 @@ struct UserListS2CPacket {
     utf user[len];
 }
 ```
+
+### EntryChange (server-to-client)
+```c
+struct EntryChangeS2CPacket {
+    uint16_t sync_id;
+    entry_change change;
+}
+```
+- `sync_id`: The sync ID of the change for locking purposes.
+- `change`: The change to apply.
\ No newline at end of file
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/ClientPacketHandler.java b/enigma-server/src/main/java/cuchaz/enigma/network/ClientPacketHandler.java
index 1b0191be..a651fe84 100644
--- a/enigma-server/src/main/java/cuchaz/enigma/network/ClientPacketHandler.java
+++ b/enigma-server/src/main/java/cuchaz/enigma/network/ClientPacketHandler.java
@@ -1,24 +1,16 @@
 package cuchaz.enigma.network;
 
-import cuchaz.enigma.analysis.EntryReference;
+import cuchaz.enigma.translation.mapping.EntryChange;
 import cuchaz.enigma.translation.mapping.EntryMapping;
 import cuchaz.enigma.translation.mapping.tree.EntryTree;
 import cuchaz.enigma.network.packet.Packet;
-import cuchaz.enigma.translation.representation.entry.Entry;
-import cuchaz.enigma.utils.validation.ValidationContext;
 
 import java.util.List;
 
 public interface ClientPacketHandler {
     void openMappings(EntryTree<EntryMapping> mappings);
 
-    void rename(ValidationContext vc, EntryReference<Entry<?>, Entry<?>> reference, String newName, boolean refreshClassTree);
-
-    void removeMapping(ValidationContext vc, EntryReference<Entry<?>, Entry<?>> reference);
-
-    void changeDocs(ValidationContext vc, EntryReference<Entry<?>, Entry<?>> reference, String updatedDocs);
-
-    void markAsDeobfuscated(ValidationContext vc, EntryReference<Entry<?>, Entry<?>> reference);
+    boolean applyChangeFromServer(EntryChange<?> change);
 
     void disconnectIfConnected(String reason);
 
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/EnigmaServer.java b/enigma-server/src/main/java/cuchaz/enigma/network/EnigmaServer.java
index 75981c3b..1ce359b6 100644
--- a/enigma-server/src/main/java/cuchaz/enigma/network/EnigmaServer.java
+++ b/enigma-server/src/main/java/cuchaz/enigma/network/EnigmaServer.java
@@ -8,6 +8,7 @@ import java.util.*;
 import java.util.concurrent.CopyOnWriteArrayList;
 
 import cuchaz.enigma.network.packet.*;
+import cuchaz.enigma.translation.mapping.EntryChange;
 import cuchaz.enigma.translation.mapping.EntryMapping;
 import cuchaz.enigma.translation.mapping.EntryRemapper;
 import cuchaz.enigma.translation.representation.entry.Entry;
@@ -16,7 +17,7 @@ public abstract class EnigmaServer {
 
         // https://discordapp.com/channels/507304429255393322/566418023372816394/700292322918793347
         public static final int DEFAULT_PORT = 34712;
-        public static final int PROTOCOL_VERSION = 0;
+        public static final int PROTOCOL_VERSION = 1;
         public static final int CHECKSUM_SIZE = 20;
         public static final int MAX_PASSWORD_LENGTH = 255; // length is written as a byte in the login packet
 
@@ -234,11 +235,11 @@ public abstract class EnigmaServer {
 
         public void sendCorrectMapping(Socket client, Entry<?> entry, boolean refreshClassTree) {
                 EntryMapping oldMapping = mappings.getDeobfMapping(entry);
-                String oldName = oldMapping == null ? null : oldMapping.getTargetName();
+                String oldName = oldMapping.targetName();
                 if (oldName == null) {
-                        sendPacket(client, new RemoveMappingS2CPacket(DUMMY_SYNC_ID, entry));
+                        sendPacket(client, new EntryChangeS2CPacket(DUMMY_SYNC_ID, EntryChange.modify(entry).clearDeobfName()));
                 } else {
-                        sendPacket(client, new RenameS2CPacket(0, entry, oldName, refreshClassTree));
+                        sendPacket(client, new EntryChangeS2CPacket(0, EntryChange.modify(entry).withDeobfName(oldName)));
                 }
         }
 
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/ChangeDocsC2SPacket.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/ChangeDocsC2SPacket.java
deleted file mode 100644
index f3e07c2d..00000000
--- a/enigma-server/src/main/java/cuchaz/enigma/network/packet/ChangeDocsC2SPacket.java
+++ /dev/null
@@ -1,64 +0,0 @@
-package cuchaz.enigma.network.packet;
-
-import java.io.DataInput;
-import java.io.DataOutput;
-import java.io.IOException;
-
-import cuchaz.enigma.translation.mapping.EntryMapping;
-import cuchaz.enigma.network.EnigmaServer;
-import cuchaz.enigma.network.Message;
-import cuchaz.enigma.network.ServerPacketHandler;
-import cuchaz.enigma.translation.representation.entry.Entry;
-import cuchaz.enigma.utils.validation.PrintValidatable;
-import cuchaz.enigma.utils.validation.ValidationContext;
-
-public class ChangeDocsC2SPacket implements Packet<ServerPacketHandler> {
-        private Entry<?> entry;
-        private String newDocs;
-
-        ChangeDocsC2SPacket() {
-        }
-
-        public ChangeDocsC2SPacket(Entry<?> entry, String newDocs) {
-                this.entry = entry;
-                this.newDocs = newDocs;
-        }
-
-        @Override
-        public void read(DataInput input) throws IOException {
-                this.entry = PacketHelper.readEntry(input);
-                this.newDocs = PacketHelper.readString(input);
-        }
-
-        @Override
-        public void write(DataOutput output) throws IOException {
-                PacketHelper.writeEntry(output, entry);
-                PacketHelper.writeString(output, newDocs);
-        }
-
-        @Override
-        public void handle(ServerPacketHandler handler) {
-                ValidationContext vc = new ValidationContext();
-                vc.setActiveElement(PrintValidatable.INSTANCE);
-
-                EntryMapping mapping = handler.getServer().getMappings().getDeobfMapping(entry);
-
-                boolean valid = handler.getServer().canModifyEntry(handler.getClient(), entry);
-                if (!valid) {
-                        String oldDocs = mapping == null ? null : mapping.getJavadoc();
-                        handler.getServer().sendPacket(handler.getClient(), new ChangeDocsS2CPacket(EnigmaServer.DUMMY_SYNC_ID, entry, oldDocs == null ? "" : oldDocs));
-                        return;
-                }
-
-                if (mapping == null) {
-                        mapping = new EntryMapping(handler.getServer().getMappings().deobfuscate(entry).getName());
-                }
-                handler.getServer().getMappings().mapFromObf(vc, entry, mapping.withDocs(newDocs.isBlank() ? null : newDocs));
-
-                if (!vc.canProceed()) return;
-
-                int syncId = handler.getServer().lockEntry(handler.getClient(), entry);
-                handler.getServer().sendToAllExcept(handler.getClient(), new ChangeDocsS2CPacket(syncId, entry, newDocs));
-                handler.getServer().sendMessage(Message.editDocs(handler.getServer().getUsername(handler.getClient()), entry));
-        }
-}
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/ChangeDocsS2CPacket.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/ChangeDocsS2CPacket.java
deleted file mode 100644
index 78fa4fa9..00000000
--- a/enigma-server/src/main/java/cuchaz/enigma/network/packet/ChangeDocsS2CPacket.java
+++ /dev/null
@@ -1,51 +0,0 @@
-package cuchaz.enigma.network.packet;
-
-import java.io.DataInput;
-import java.io.DataOutput;
-import java.io.IOException;
-
-import cuchaz.enigma.analysis.EntryReference;
-import cuchaz.enigma.network.ClientPacketHandler;
-import cuchaz.enigma.translation.representation.entry.Entry;
-import cuchaz.enigma.utils.validation.PrintValidatable;
-import cuchaz.enigma.utils.validation.ValidationContext;
-
-public class ChangeDocsS2CPacket implements Packet<ClientPacketHandler> {
-        private int syncId;
-        private Entry<?> entry;
-        private String newDocs;
-
-        ChangeDocsS2CPacket() {
-        }
-
-        public ChangeDocsS2CPacket(int syncId, Entry<?> entry, String newDocs) {
-                this.syncId = syncId;
-                this.entry = entry;
-                this.newDocs = newDocs;
-        }
-
-        @Override
-        public void read(DataInput input) throws IOException {
-                this.syncId = input.readUnsignedShort();
-                this.entry = PacketHelper.readEntry(input);
-                this.newDocs = PacketHelper.readString(input);
-        }
-
-        @Override
-        public void write(DataOutput output) throws IOException {
-                output.writeShort(syncId);
-                PacketHelper.writeEntry(output, entry);
-                PacketHelper.writeString(output, newDocs);
-        }
-
-        @Override
-        public void handle(ClientPacketHandler controller) {
-                ValidationContext vc = new ValidationContext();
-                vc.setActiveElement(PrintValidatable.INSTANCE);
-
-                controller.changeDocs(vc, new EntryReference<>(entry, entry.getName()), newDocs);
-
-                if (!vc.canProceed()) return;
-                controller.sendPacket(new ConfirmChangeC2SPacket(syncId));
-        }
-}
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/EntryChangeC2SPacket.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/EntryChangeC2SPacket.java
new file mode 100644
index 00000000..b97877c6
--- /dev/null
+++ b/enigma-server/src/main/java/cuchaz/enigma/network/packet/EntryChangeC2SPacket.java
@@ -0,0 +1,66 @@
+package cuchaz.enigma.network.packet;
+
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.io.IOException;
+
+import cuchaz.enigma.network.Message;
+import cuchaz.enigma.network.ServerPacketHandler;
+import cuchaz.enigma.translation.mapping.EntryChange;
+import cuchaz.enigma.translation.mapping.EntryUtil;
+import cuchaz.enigma.utils.validation.PrintValidatable;
+import cuchaz.enigma.utils.validation.ValidationContext;
+
+public class EntryChangeC2SPacket implements Packet<ServerPacketHandler> {
+
+        private EntryChange<?> change;
+
+        EntryChangeC2SPacket() {
+        }
+
+        public EntryChangeC2SPacket(EntryChange<?> change) {
+                this.change = change;
+        }
+
+        @Override
+        public void read(DataInput input) throws IOException {
+                this.change = PacketHelper.readEntryChange(input);
+        }
+
+        @Override
+        public void write(DataOutput output) throws IOException {
+                PacketHelper.writeEntryChange(output, change);
+        }
+
+        @Override
+        public void handle(ServerPacketHandler handler) {
+                ValidationContext vc = new ValidationContext();
+                vc.setActiveElement(PrintValidatable.INSTANCE);
+
+                boolean valid = handler.getServer().canModifyEntry(handler.getClient(), this.change.getTarget());
+
+                if (valid) {
+                        EntryUtil.applyChange(vc, handler.getServer().getMappings(), this.change);
+                        valid = vc.canProceed();
+                }
+
+                if (!valid) {
+                        handler.getServer().sendCorrectMapping(handler.getClient(), this.change.getTarget(), true);
+                        return;
+                }
+
+                int syncId = handler.getServer().lockEntry(handler.getClient(), this.change.getTarget());
+                handler.getServer().sendToAllExcept(handler.getClient(), new EntryChangeS2CPacket(syncId, this.change));
+
+                if (this.change.getDeobfName().isSet()) {
+                        handler.getServer().sendMessage(Message.rename(handler.getServer().getUsername(handler.getClient()), this.change.getTarget(), this.change.getDeobfName().getNewValue()));
+                } else if (this.change.getDeobfName().isReset()) {
+                        handler.getServer().sendMessage(Message.removeMapping(handler.getServer().getUsername(handler.getClient()), this.change.getTarget()));
+                }
+
+                if (!this.change.getJavadoc().isUnchanged()) {
+                        handler.getServer().sendMessage(Message.editDocs(handler.getServer().getUsername(handler.getClient()), this.change.getTarget()));
+                }
+        }
+
+}
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/EntryChangeS2CPacket.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/EntryChangeS2CPacket.java
new file mode 100644
index 00000000..a237b916
--- /dev/null
+++ b/enigma-server/src/main/java/cuchaz/enigma/network/packet/EntryChangeS2CPacket.java
@@ -0,0 +1,42 @@
+package cuchaz.enigma.network.packet;
+
+import java.io.DataInput;
+import java.io.DataOutput;
+import java.io.IOException;
+
+import cuchaz.enigma.network.ClientPacketHandler;
+import cuchaz.enigma.translation.mapping.EntryChange;
+
+public class EntryChangeS2CPacket implements Packet<ClientPacketHandler> {
+
+        private int syncId;
+        private EntryChange<?> change;
+
+        public EntryChangeS2CPacket(int syncId, EntryChange<?> change) {
+                this.syncId = syncId;
+                this.change = change;
+        }
+
+        EntryChangeS2CPacket() {
+        }
+
+        @Override
+        public void read(DataInput input) throws IOException {
+                this.syncId = input.readUnsignedShort();
+                this.change = PacketHelper.readEntryChange(input);
+        }
+
+        @Override
+        public void write(DataOutput output) throws IOException {
+                output.writeShort(this.syncId);
+                PacketHelper.writeEntryChange(output, this.change);
+        }
+
+        @Override
+        public void handle(ClientPacketHandler handler) {
+                if (handler.applyChangeFromServer(this.change)) {
+                        handler.sendPacket(new ConfirmChangeC2SPacket(this.syncId));
+                }
+        }
+
+}
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/MarkDeobfuscatedC2SPacket.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/MarkDeobfuscatedC2SPacket.java
deleted file mode 100644
index 732c7448..00000000
--- a/enigma-server/src/main/java/cuchaz/enigma/network/packet/MarkDeobfuscatedC2SPacket.java
+++ /dev/null
@@ -1,56 +0,0 @@
-package cuchaz.enigma.network.packet;
-
-import java.io.DataInput;
-import java.io.DataOutput;
-import java.io.IOException;
-
-import cuchaz.enigma.network.Message;
-import cuchaz.enigma.network.ServerPacketHandler;
-import cuchaz.enigma.translation.mapping.EntryMapping;
-import cuchaz.enigma.translation.representation.entry.Entry;
-import cuchaz.enigma.utils.validation.PrintValidatable;
-import cuchaz.enigma.utils.validation.ValidationContext;
-
-public class MarkDeobfuscatedC2SPacket implements Packet<ServerPacketHandler> {
-        private Entry<?> entry;
-
-        MarkDeobfuscatedC2SPacket() {
-        }
-
-        public MarkDeobfuscatedC2SPacket(Entry<?> entry) {
-                this.entry = entry;
-        }
-
-        @Override
-        public void read(DataInput input) throws IOException {
-                this.entry = PacketHelper.readEntry(input);
-        }
-
-        @Override
-        public void write(DataOutput output) throws IOException {
-                PacketHelper.writeEntry(output, entry);
-        }
-
-        @Override
-        public void handle(ServerPacketHandler handler) {
-                ValidationContext vc = new ValidationContext();
-                vc.setActiveElement(PrintValidatable.INSTANCE);
-
-                boolean valid = handler.getServer().canModifyEntry(handler.getClient(), entry);
-
-                if (!valid) {
-                        handler.getServer().sendCorrectMapping(handler.getClient(), entry, true);
-                        return;
-                }
-
-                handler.getServer().getMappings().mapFromObf(vc, entry, new EntryMapping(handler.getServer().getMappings().deobfuscate(entry).getName()));
-
-                if (!vc.canProceed()) return;
-
-                handler.getServer().log(handler.getServer().getUsername(handler.getClient()) + " marked " + entry + " as deobfuscated");
-
-                int syncId = handler.getServer().lockEntry(handler.getClient(), entry);
-                handler.getServer().sendToAllExcept(handler.getClient(), new MarkDeobfuscatedS2CPacket(syncId, entry));
-                handler.getServer().sendMessage(Message.markDeobf(handler.getServer().getUsername(handler.getClient()), entry));
-        }
-}
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/MarkDeobfuscatedS2CPacket.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/MarkDeobfuscatedS2CPacket.java
deleted file mode 100644
index 969d13c5..00000000
--- a/enigma-server/src/main/java/cuchaz/enigma/network/packet/MarkDeobfuscatedS2CPacket.java
+++ /dev/null
@@ -1,47 +0,0 @@
-package cuchaz.enigma.network.packet;
-
-import java.io.DataInput;
-import java.io.DataOutput;
-import java.io.IOException;
-
-import cuchaz.enigma.analysis.EntryReference;
-import cuchaz.enigma.network.ClientPacketHandler;
-import cuchaz.enigma.translation.representation.entry.Entry;
-import cuchaz.enigma.utils.validation.PrintValidatable;
-import cuchaz.enigma.utils.validation.ValidationContext;
-
-public class MarkDeobfuscatedS2CPacket implements Packet<ClientPacketHandler> {
-        private int syncId;
-        private Entry<?> entry;
-
-        MarkDeobfuscatedS2CPacket() {
-        }
-
-        public MarkDeobfuscatedS2CPacket(int syncId, Entry<?> entry) {
-                this.syncId = syncId;
-                this.entry = entry;
-        }
-
-        @Override
-        public void read(DataInput input) throws IOException {
-                this.syncId = input.readUnsignedShort();
-                this.entry = PacketHelper.readEntry(input);
-        }
-
-        @Override
-        public void write(DataOutput output) throws IOException {
-                output.writeShort(syncId);
-                PacketHelper.writeEntry(output, entry);
-        }
-
-        @Override
-        public void handle(ClientPacketHandler controller) {
-                ValidationContext vc = new ValidationContext();
-                vc.setActiveElement(PrintValidatable.INSTANCE);
-
-                controller.markAsDeobfuscated(vc, new EntryReference<>(entry, entry.getName()));
-
-                if (!vc.canProceed()) return;
-                controller.sendPacket(new ConfirmChangeC2SPacket(syncId));
-        }
-}
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/PacketHelper.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/PacketHelper.java
index 464606e0..2649cdc4 100644
--- a/enigma-server/src/main/java/cuchaz/enigma/network/packet/PacketHelper.java
+++ b/enigma-server/src/main/java/cuchaz/enigma/network/packet/PacketHelper.java
@@ -1,18 +1,17 @@
 package cuchaz.enigma.network.packet;
 
-import cuchaz.enigma.translation.representation.MethodDescriptor;
-import cuchaz.enigma.translation.representation.TypeDescriptor;
-import cuchaz.enigma.translation.representation.entry.ClassEntry;
-import cuchaz.enigma.translation.representation.entry.Entry;
-import cuchaz.enigma.translation.representation.entry.FieldEntry;
-import cuchaz.enigma.translation.representation.entry.LocalVariableEntry;
-import cuchaz.enigma.translation.representation.entry.MethodEntry;
-
 import java.io.DataInput;
 import java.io.DataOutput;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 
+import cuchaz.enigma.translation.mapping.AccessModifier;
+import cuchaz.enigma.translation.mapping.EntryChange;
+import cuchaz.enigma.translation.representation.MethodDescriptor;
+import cuchaz.enigma.translation.representation.TypeDescriptor;
+import cuchaz.enigma.translation.representation.entry.*;
+import cuchaz.enigma.utils.TristateChange;
+
 public class PacketHelper {
 
         private static final int ENTRY_CLASS = 0, ENTRY_FIELD = 1, ENTRY_METHOD = 2, ENTRY_LOCAL_VAR = 3;
@@ -37,35 +36,40 @@ public class PacketHelper {
                 }
 
                 switch (type) {
-                case ENTRY_CLASS: {
-                        if (parent != null && !(parent instanceof ClassEntry)) {
-                                throw new IOException("Class requires class parent");
+                        case ENTRY_CLASS: {
+                                if (parent != null && !(parent instanceof ClassEntry)) {
+                                        throw new IOException("Class requires class parent");
+                                }
+
+                                return new ClassEntry((ClassEntry) parent, name, javadocs);
                         }
-                        return new ClassEntry((ClassEntry) parent, name, javadocs);
-                }
-                case ENTRY_FIELD: {
-                        if (!(parent instanceof ClassEntry)) {
-                                throw new IOException("Field requires class parent");
+                        case ENTRY_FIELD: {
+                                if (!(parent instanceof ClassEntry parentClass)) {
+                                        throw new IOException("Field requires class parent");
+                                }
+
+                                TypeDescriptor desc = new TypeDescriptor(readString(input));
+                                return new FieldEntry(parentClass, name, desc, javadocs);
                         }
-                        TypeDescriptor desc = new TypeDescriptor(readString(input));
-                        return new FieldEntry((ClassEntry) parent, name, desc, javadocs);
-                }
-                case ENTRY_METHOD: {
-                        if (!(parent instanceof ClassEntry)) {
-                                throw new IOException("Method requires class parent");
+                        case ENTRY_METHOD: {
+                                if (!(parent instanceof ClassEntry parentClass)) {
+                                        throw new IOException("Method requires class parent");
+                                }
+
+                                MethodDescriptor desc = new MethodDescriptor(readString(input));
+                                return new MethodEntry(parentClass, name, desc, javadocs);
                         }
-                        MethodDescriptor desc = new MethodDescriptor(readString(input));
-                        return new MethodEntry((ClassEntry) parent, name, desc, javadocs);
-                }
-                case ENTRY_LOCAL_VAR: {
-                        if (!(parent instanceof MethodEntry)) {
-                                throw new IOException("Local variable requires method parent");
+                        case ENTRY_LOCAL_VAR: {
+                                if (!(parent instanceof MethodEntry parentMethod)) {
+                                        throw new IOException("Local variable requires method parent");
+                                }
+
+                                int index = input.readUnsignedShort();
+                                boolean parameter = input.readBoolean();
+                                return new LocalVariableEntry(parentMethod, index, name, parameter, javadocs);
                         }
-                        int index = input.readUnsignedShort();
-                        boolean parameter = input.readBoolean();
-                        return new LocalVariableEntry((MethodEntry) parent, index, name, parameter, javadocs);
-                }
-                default: throw new IOException("Received unknown entry type " + type);
+                        default:
+                                throw new IOException("Received unknown entry type " + type);
                 }
         }
 
@@ -132,4 +136,64 @@ public class PacketHelper {
                 output.write(bytes);
         }
 
+        public static EntryChange<?> readEntryChange(DataInput input) throws IOException {
+                Entry<?> e = readEntry(input);
+                EntryChange<?> change = EntryChange.modify(e);
+
+                int flags = input.readUnsignedByte();
+                TristateChange.Type deobfNameT = TristateChange.Type.values()[flags & 0x3];
+                TristateChange.Type accessT = TristateChange.Type.values()[flags >> 2 & 0x3];
+                TristateChange.Type javadocT = TristateChange.Type.values()[flags >> 4 & 0x3];
+
+                switch (deobfNameT) {
+                        case RESET:
+                                change = change.clearDeobfName();
+                                break;
+                        case SET:
+                                change = change.withDeobfName(readString(input));
+                                break;
+                }
+
+                switch (accessT) {
+                        case RESET:
+                                change = change.clearAccess();
+                                break;
+                        case SET:
+                                change = change.withAccess(AccessModifier.values()[flags >> 6 & 0x3]);
+                                break;
+                }
+
+                switch (javadocT) {
+                        case RESET:
+                                change = change.clearJavadoc();
+                                break;
+                        case SET:
+                                change = change.withJavadoc(readString(input));
+                                break;
+                }
+
+                return change;
+        }
+
+        public static void writeEntryChange(DataOutput output, EntryChange<?> change) throws IOException {
+                writeEntry(output, change.getTarget());
+                int flags = change.getDeobfName().getType().ordinal() |
+                                change.getAccess().getType().ordinal() << 2 |
+                                change.getJavadoc().getType().ordinal() << 4;
+
+                if (change.getAccess().isSet()) {
+                        flags |= change.getAccess().getNewValue().ordinal() << 6;
+                }
+
+                output.writeByte(flags);
+
+                if (change.getDeobfName().isSet()) {
+                        writeString(output, change.getDeobfName().getNewValue());
+                }
+
+                if (change.getJavadoc().isSet()) {
+                        writeString(output, change.getJavadoc().getNewValue());
+                }
+        }
+
 }
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/PacketRegistry.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/PacketRegistry.java
index 3b8af81c..59999ccc 100644
--- a/enigma-server/src/main/java/cuchaz/enigma/network/packet/PacketRegistry.java
+++ b/enigma-server/src/main/java/cuchaz/enigma/network/packet/PacketRegistry.java
@@ -1,12 +1,12 @@
 package cuchaz.enigma.network.packet;
 
-import cuchaz.enigma.network.ClientPacketHandler;
-import cuchaz.enigma.network.ServerPacketHandler;
-
 import java.util.HashMap;
 import java.util.Map;
 import java.util.function.Supplier;
 
+import cuchaz.enigma.network.ClientPacketHandler;
+import cuchaz.enigma.network.ServerPacketHandler;
+
 public class PacketRegistry {
 
         private static final Map<Class<? extends Packet<ServerPacketHandler>>, Integer> c2sPacketIds = new HashMap<>();
@@ -27,20 +27,14 @@ public class PacketRegistry {
         static {
                 registerC2S(0, LoginC2SPacket.class, LoginC2SPacket::new);
                 registerC2S(1, ConfirmChangeC2SPacket.class, ConfirmChangeC2SPacket::new);
-                registerC2S(2, RenameC2SPacket.class, RenameC2SPacket::new);
-                registerC2S(3, RemoveMappingC2SPacket.class, RemoveMappingC2SPacket::new);
-                registerC2S(4, ChangeDocsC2SPacket.class, ChangeDocsC2SPacket::new);
-                registerC2S(5, MarkDeobfuscatedC2SPacket.class, MarkDeobfuscatedC2SPacket::new);
                 registerC2S(6, MessageC2SPacket.class, MessageC2SPacket::new);
+                registerC2S(7, EntryChangeC2SPacket.class, EntryChangeC2SPacket::new);
 
                 registerS2C(0, KickS2CPacket.class, KickS2CPacket::new);
                 registerS2C(1, SyncMappingsS2CPacket.class, SyncMappingsS2CPacket::new);
-                registerS2C(2, RenameS2CPacket.class, RenameS2CPacket::new);
-                registerS2C(3, RemoveMappingS2CPacket.class, RemoveMappingS2CPacket::new);
-                registerS2C(4, ChangeDocsS2CPacket.class, ChangeDocsS2CPacket::new);
-                registerS2C(5, MarkDeobfuscatedS2CPacket.class, MarkDeobfuscatedS2CPacket::new);
                 registerS2C(6, MessageS2CPacket.class, MessageS2CPacket::new);
                 registerS2C(7, UserListS2CPacket.class, UserListS2CPacket::new);
+                registerS2C(8, EntryChangeS2CPacket.class, EntryChangeS2CPacket::new);
         }
 
         public static int getC2SId(Packet<ServerPacketHandler> packet) {
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/RemoveMappingC2SPacket.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/RemoveMappingC2SPacket.java
deleted file mode 100644
index 298e674f..00000000
--- a/enigma-server/src/main/java/cuchaz/enigma/network/packet/RemoveMappingC2SPacket.java
+++ /dev/null
@@ -1,56 +0,0 @@
-package cuchaz.enigma.network.packet;
-
-import java.io.DataInput;
-import java.io.DataOutput;
-import java.io.IOException;
-
-import cuchaz.enigma.network.Message;
-import cuchaz.enigma.network.ServerPacketHandler;
-import cuchaz.enigma.translation.representation.entry.Entry;
-import cuchaz.enigma.utils.validation.PrintValidatable;
-import cuchaz.enigma.utils.validation.ValidationContext;
-
-public class RemoveMappingC2SPacket implements Packet<ServerPacketHandler> {
-        private Entry<?> entry;
-
-        RemoveMappingC2SPacket() {
-        }
-
-        public RemoveMappingC2SPacket(Entry<?> entry) {
-                this.entry = entry;
-        }
-
-        @Override
-        public void read(DataInput input) throws IOException {
-                this.entry = PacketHelper.readEntry(input);
-        }
-
-        @Override
-        public void write(DataOutput output) throws IOException {
-                PacketHelper.writeEntry(output, entry);
-        }
-
-        @Override
-        public void handle(ServerPacketHandler handler) {
-                ValidationContext vc = new ValidationContext();
-                vc.setActiveElement(PrintValidatable.INSTANCE);
-
-                boolean valid = handler.getServer().canModifyEntry(handler.getClient(), entry);
-
-                if (valid) {
-                        handler.getServer().getMappings().removeByObf(vc, entry);
-                        valid = vc.canProceed();
-                }
-
-                if (!valid) {
-                        handler.getServer().sendCorrectMapping(handler.getClient(), entry, true);
-                        return;
-                }
-
-                handler.getServer().log(handler.getServer().getUsername(handler.getClient()) + " removed the mapping for " + entry);
-
-                int syncId = handler.getServer().lockEntry(handler.getClient(), entry);
-                handler.getServer().sendToAllExcept(handler.getClient(), new RemoveMappingS2CPacket(syncId, entry));
-                handler.getServer().sendMessage(Message.removeMapping(handler.getServer().getUsername(handler.getClient()), entry));
-        }
-}
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/RemoveMappingS2CPacket.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/RemoveMappingS2CPacket.java
deleted file mode 100644
index e336c7b2..00000000
--- a/enigma-server/src/main/java/cuchaz/enigma/network/packet/RemoveMappingS2CPacket.java
+++ /dev/null
@@ -1,47 +0,0 @@
-package cuchaz.enigma.network.packet;
-
-import java.io.DataInput;
-import java.io.DataOutput;
-import java.io.IOException;
-
-import cuchaz.enigma.analysis.EntryReference;
-import cuchaz.enigma.network.ClientPacketHandler;
-import cuchaz.enigma.translation.representation.entry.Entry;
-import cuchaz.enigma.utils.validation.PrintValidatable;
-import cuchaz.enigma.utils.validation.ValidationContext;
-
-public class RemoveMappingS2CPacket implements Packet<ClientPacketHandler> {
-        private int syncId;
-        private Entry<?> entry;
-
-        RemoveMappingS2CPacket() {
-        }
-
-        public RemoveMappingS2CPacket(int syncId, Entry<?> entry) {
-                this.syncId = syncId;
-                this.entry = entry;
-        }
-
-        @Override
-        public void read(DataInput input) throws IOException {
-                this.syncId = input.readUnsignedShort();
-                this.entry = PacketHelper.readEntry(input);
-        }
-
-        @Override
-        public void write(DataOutput output) throws IOException {
-                output.writeShort(syncId);
-                PacketHelper.writeEntry(output, entry);
-        }
-
-        @Override
-        public void handle(ClientPacketHandler controller) {
-                ValidationContext vc = new ValidationContext();
-                vc.setActiveElement(PrintValidatable.INSTANCE);
-
-                controller.removeMapping(vc, new EntryReference<>(entry, entry.getName()));
-
-                if (!vc.canProceed()) return;
-                controller.sendPacket(new ConfirmChangeC2SPacket(syncId));
-        }
-}
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/RenameC2SPacket.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/RenameC2SPacket.java
deleted file mode 100644
index 694d4321..00000000
--- a/enigma-server/src/main/java/cuchaz/enigma/network/packet/RenameC2SPacket.java
+++ /dev/null
@@ -1,66 +0,0 @@
-package cuchaz.enigma.network.packet;
-
-import java.io.DataInput;
-import java.io.DataOutput;
-import java.io.IOException;
-
-import cuchaz.enigma.network.Message;
-import cuchaz.enigma.network.ServerPacketHandler;
-import cuchaz.enigma.translation.mapping.EntryMapping;
-import cuchaz.enigma.translation.representation.entry.Entry;
-import cuchaz.enigma.utils.validation.PrintValidatable;
-import cuchaz.enigma.utils.validation.ValidationContext;
-
-public class RenameC2SPacket implements Packet<ServerPacketHandler> {
-        private Entry<?> entry;
-        private String newName;
-        private boolean refreshClassTree;
-
-        RenameC2SPacket() {
-        }
-
-        public RenameC2SPacket(Entry<?> entry, String newName, boolean refreshClassTree) {
-                this.entry = entry;
-                this.newName = newName;
-                this.refreshClassTree = refreshClassTree;
-        }
-
-        @Override
-        public void read(DataInput input) throws IOException {
-                this.entry = PacketHelper.readEntry(input);
-                this.newName = PacketHelper.readString(input);
-                this.refreshClassTree = input.readBoolean();
-        }
-
-        @Override
-        public void write(DataOutput output) throws IOException {
-                PacketHelper.writeEntry(output, entry);
-                PacketHelper.writeString(output, newName);
-                output.writeBoolean(refreshClassTree);
-        }
-
-        @Override
-        public void handle(ServerPacketHandler handler) {
-                ValidationContext vc = new ValidationContext();
-                vc.setActiveElement(PrintValidatable.INSTANCE);
-
-                boolean valid = handler.getServer().canModifyEntry(handler.getClient(), entry);
-
-                if (valid) {
-                        EntryMapping previous = handler.getServer().getMappings().getDeobfMapping(entry);
-                        handler.getServer().getMappings().mapFromObf(vc, entry, previous != null ? previous.withName(newName) : new EntryMapping(newName));
-                        valid = vc.canProceed();
-                }
-
-                if (!valid) {
-                        handler.getServer().sendCorrectMapping(handler.getClient(), entry, refreshClassTree);
-                        return;
-                }
-
-                handler.getServer().log(handler.getServer().getUsername(handler.getClient()) + " renamed " + entry + " to " + newName);
-
-                int syncId = handler.getServer().lockEntry(handler.getClient(), entry);
-                handler.getServer().sendToAllExcept(handler.getClient(), new RenameS2CPacket(syncId, entry, newName, refreshClassTree));
-                handler.getServer().sendMessage(Message.rename(handler.getServer().getUsername(handler.getClient()), entry, newName));
-        }
-}
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/RenameS2CPacket.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/RenameS2CPacket.java
deleted file mode 100644
index fdf06540..00000000
--- a/enigma-server/src/main/java/cuchaz/enigma/network/packet/RenameS2CPacket.java
+++ /dev/null
@@ -1,55 +0,0 @@
-package cuchaz.enigma.network.packet;
-
-import java.io.DataInput;
-import java.io.DataOutput;
-import java.io.IOException;
-
-import cuchaz.enigma.analysis.EntryReference;
-import cuchaz.enigma.network.ClientPacketHandler;
-import cuchaz.enigma.translation.representation.entry.Entry;
-import cuchaz.enigma.utils.validation.PrintValidatable;
-import cuchaz.enigma.utils.validation.ValidationContext;
-
-public class RenameS2CPacket implements Packet<ClientPacketHandler> {
-        private int syncId;
-        private Entry<?> entry;
-        private String newName;
-        private boolean refreshClassTree;
-
-        RenameS2CPacket() {
-        }
-
-        public RenameS2CPacket(int syncId, Entry<?> entry, String newName, boolean refreshClassTree) {
-                this.syncId = syncId;
-                this.entry = entry;
-                this.newName = newName;
-                this.refreshClassTree = refreshClassTree;
-        }
-
-        @Override
-        public void read(DataInput input) throws IOException {
-                this.syncId = input.readUnsignedShort();
-                this.entry = PacketHelper.readEntry(input);
-                this.newName = PacketHelper.readString(input);
-                this.refreshClassTree = input.readBoolean();
-        }
-
-        @Override
-        public void write(DataOutput output) throws IOException {
-                output.writeShort(syncId);
-                PacketHelper.writeEntry(output, entry);
-                PacketHelper.writeString(output, newName);
-                output.writeBoolean(refreshClassTree);
-        }
-
-        @Override
-        public void handle(ClientPacketHandler controller) {
-                ValidationContext vc = new ValidationContext();
-                vc.setActiveElement(PrintValidatable.INSTANCE);
-
-                controller.rename(vc, new EntryReference<>(entry, entry.getName()), newName, refreshClassTree);
-
-                if (!vc.canProceed()) return;
-                controller.sendPacket(new ConfirmChangeC2SPacket(syncId));
-        }
-}
diff --git a/enigma-server/src/main/java/cuchaz/enigma/network/packet/SyncMappingsS2CPacket.java b/enigma-server/src/main/java/cuchaz/enigma/network/packet/SyncMappingsS2CPacket.java
index 92a78748..6d9c0bcb 100644
--- a/enigma-server/src/main/java/cuchaz/enigma/network/packet/SyncMappingsS2CPacket.java
+++ b/enigma-server/src/main/java/cuchaz/enigma/network/packet/SyncMappingsS2CPacket.java
@@ -1,19 +1,19 @@
 package cuchaz.enigma.network.packet;
 
-import cuchaz.enigma.translation.mapping.EntryMapping;
-import cuchaz.enigma.translation.mapping.tree.EntryTree;
-import cuchaz.enigma.translation.mapping.tree.EntryTreeNode;
-import cuchaz.enigma.translation.mapping.tree.HashEntryTree;
-import cuchaz.enigma.network.ClientPacketHandler;
-import cuchaz.enigma.network.EnigmaServer;
-import cuchaz.enigma.translation.representation.entry.Entry;
-
 import java.io.DataInput;
 import java.io.DataOutput;
 import java.io.IOException;
 import java.util.Collection;
 import java.util.List;
 
+import cuchaz.enigma.network.ClientPacketHandler;
+import cuchaz.enigma.network.EnigmaServer;
+import cuchaz.enigma.translation.mapping.EntryMapping;
+import cuchaz.enigma.translation.mapping.tree.EntryTree;
+import cuchaz.enigma.translation.mapping.tree.EntryTreeNode;
+import cuchaz.enigma.translation.mapping.tree.HashEntryTree;
+import cuchaz.enigma.translation.representation.entry.Entry;
+
 public class SyncMappingsS2CPacket implements Packet<ClientPacketHandler> {
         private EntryTree<EntryMapping> mappings;
 
@@ -35,16 +35,9 @@ public class SyncMappingsS2CPacket implements Packet<ClientPacketHandler> {
 
         private void readEntryTreeNode(DataInput input, Entry<?> parent) throws IOException {
                 Entry<?> entry = PacketHelper.readEntry(input, parent, false);
-                EntryMapping mapping = null;
-                if (input.readBoolean()) {
-                        String name = input.readUTF();
-                        if (input.readBoolean()) {
-                                String javadoc = input.readUTF();
-                                mapping = new EntryMapping(name, javadoc);
-                        } else {
-                                mapping = new EntryMapping(name);
-                        }
-                }
+                String name = PacketHelper.readString(input);
+                String javadoc = PacketHelper.readString(input);
+                EntryMapping mapping = new EntryMapping(!name.isEmpty() ? name : null, !javadoc.isEmpty() ? javadoc : null);
                 mappings.insert(entry, mapping);
                 int size = input.readUnsignedShort();
                 for (int i = 0; i < size; i++) {
@@ -64,14 +57,10 @@ public class SyncMappingsS2CPacket implements Packet<ClientPacketHandler> {
         private static void writeEntryTreeNode(DataOutput output, EntryTreeNode<EntryMapping> node) throws IOException {
                 PacketHelper.writeEntry(output, node.getEntry(), false);
                 EntryMapping value = node.getValue();
-                output.writeBoolean(value != null);
-                if (value != null) {
-                        PacketHelper.writeString(output, value.getTargetName());
-                        output.writeBoolean(value.getJavadoc() != null);
-                        if (value.getJavadoc() != null) {
-                                PacketHelper.writeString(output, value.getJavadoc());
-                        }
-                }
+                if (value == null) value = EntryMapping.DEFAULT;
+
+                PacketHelper.writeString(output, value.targetName() != null ? value.targetName() : "");
+                PacketHelper.writeString(output, value.javadoc() != null ? value.javadoc() : "");
                 Collection<? extends EntryTreeNode<EntryMapping>> children = node.getChildNodes();
                 output.writeShort(children.size());
                 for (EntryTreeNode<EntryMapping> child : children) {
diff --git a/enigma-swing/src/main/java/cuchaz/enigma/gui/Gui.java b/enigma-swing/src/main/java/cuchaz/enigma/gui/Gui.java
index a657d171..cddedad7 100644
--- a/enigma-swing/src/main/java/cuchaz/enigma/gui/Gui.java
+++ b/enigma-swing/src/main/java/cuchaz/enigma/gui/Gui.java
@@ -49,11 +49,9 @@ import cuchaz.enigma.gui.renderer.InheritanceTreeCellRenderer;
 import cuchaz.enigma.gui.renderer.MessageListCellRenderer;
 import cuchaz.enigma.gui.util.*;
 import cuchaz.enigma.network.Message;
-import cuchaz.enigma.network.packet.MarkDeobfuscatedC2SPacket;
 import cuchaz.enigma.network.packet.MessageC2SPacket;
-import cuchaz.enigma.network.packet.RemoveMappingC2SPacket;
-import cuchaz.enigma.network.packet.RenameC2SPacket;
 import cuchaz.enigma.source.Token;
+import cuchaz.enigma.translation.mapping.EntryChange;
 import cuchaz.enigma.translation.mapping.EntryRemapper;
 import cuchaz.enigma.translation.representation.entry.ClassEntry;
 import cuchaz.enigma.translation.representation.entry.Entry;
@@ -740,12 +738,10 @@ public class Gui implements LanguageChangeListener {
 
                 Entry<?> obfEntry = cursorReference.entry;
 
-                if (controller.project.getMapper().extendedDeobfuscate(obfEntry).isDeobfuscated()) {
-                        if (!validateImmediateAction(vc -> this.controller.removeMapping(vc, cursorReference))) return;
-                        this.controller.sendPacket(new RemoveMappingC2SPacket(cursorReference.getNameableEntry()));
+                if (this.controller.project.getMapper().getDeobfMapping(obfEntry).targetName() != null) {
+                        validateImmediateAction(vc -> this.controller.applyChange(vc, EntryChange.modify(obfEntry).clearDeobfName()));
                 } else {
-                        if (!validateImmediateAction(vc -> this.controller.markAsDeobfuscated(vc, cursorReference))) return;
-                        this.controller.sendPacket(new MarkDeobfuscatedC2SPacket(cursorReference.getNameableEntry()));
+                        validateImmediateAction(vc -> this.controller.applyChange(vc, EntryChange.modify(obfEntry).withDefaultDeobfName(this.getController().project)));
                 }
         }
 
@@ -813,7 +809,7 @@ public class Gui implements LanguageChangeListener {
                 this.frame.repaint();
         }
 
-        public void onPanelRename(ValidationContext vc, Object prevData, Object data, DefaultMutableTreeNode node) {
+        public void onRenameFromClassTree(ValidationContext vc, Object prevData, Object data, DefaultMutableTreeNode node) {
                 if (data instanceof String) {
                         // package rename
                         for (int i = 0; i < node.getChildCount(); i++) {
@@ -821,7 +817,7 @@ public class Gui implements LanguageChangeListener {
                                 ClassEntry prevDataChild = (ClassEntry) childNode.getUserObject();
                                 ClassEntry dataChild = new ClassEntry(data + "/" + prevDataChild.getSimpleName());
 
-                                onPanelRename(vc, prevDataChild, dataChild, node);
+                                onRenameFromClassTree(vc, prevDataChild, dataChild, node);
                         }
                         node.setUserObject(data);
                         // Ob package will never be modified, just reload deob view
@@ -839,9 +835,9 @@ public class Gui implements LanguageChangeListener {
                                         .filter(e -> mapper.deobfuscate(e).equals(deobf))
                                         .findAny().orElse(deobf);
 
-                        this.controller.rename(vc, new EntryReference<>(obf, obf.getFullName()), ((ClassEntry) data).getFullName(), false);
-                        if (!vc.canProceed()) return;
-                        this.controller.sendPacket(new RenameC2SPacket(obf, ((ClassEntry) data).getFullName(), false));
+                        this.controller.applyChange(vc, EntryChange.modify(obf).withDeobfName(((ClassEntry) data).getFullName()));
+                } else {
+                        throw new IllegalStateException(String.format("unhandled rename object data: '%s'", data));
                 }
         }
 
diff --git a/enigma-swing/src/main/java/cuchaz/enigma/gui/GuiController.java b/enigma-swing/src/main/java/cuchaz/enigma/gui/GuiController.java
index 2b75655a..4a15b418 100644
--- a/enigma-swing/src/main/java/cuchaz/enigma/gui/GuiController.java
+++ b/enigma-swing/src/main/java/cuchaz/enigma/gui/GuiController.java
@@ -18,6 +18,7 @@ import java.io.IOException;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
+import java.util.Objects;
 import java.util.Set;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutionException;
@@ -39,10 +40,12 @@ import cuchaz.enigma.classprovider.ClasspathClassProvider;
 import cuchaz.enigma.gui.config.NetConfig;
 import cuchaz.enigma.gui.config.UiConfig;
 import cuchaz.enigma.gui.dialog.ProgressDialog;
+import cuchaz.enigma.gui.newabstraction.EntryValidation;
 import cuchaz.enigma.gui.stats.StatsGenerator;
 import cuchaz.enigma.gui.stats.StatsMember;
 import cuchaz.enigma.gui.util.History;
 import cuchaz.enigma.network.*;
+import cuchaz.enigma.network.packet.EntryChangeC2SPacket;
 import cuchaz.enigma.network.packet.LoginC2SPacket;
 import cuchaz.enigma.network.packet.Packet;
 import cuchaz.enigma.source.DecompiledClassSource;
@@ -62,6 +65,7 @@ import cuchaz.enigma.translation.representation.entry.FieldEntry;
 import cuchaz.enigma.translation.representation.entry.MethodEntry;
 import cuchaz.enigma.utils.I18n;
 import cuchaz.enigma.utils.Utils;
+import cuchaz.enigma.utils.validation.PrintValidatable;
 import cuchaz.enigma.utils.validation.ValidationContext;
 
 public class GuiController implements ClientPacketHandler {
@@ -401,19 +405,6 @@ public class GuiController implements ClientPacketHandler {
                 });
         }
 
-        public void onModifierChanged(ValidationContext vc, Entry<?> entry, AccessModifier modifier) {
-                EntryRemapper mapper = project.getMapper();
-
-                EntryMapping mapping = mapper.getDeobfMapping(entry);
-                if (mapping != null) {
-                        mapper.mapFromObf(vc, entry, new EntryMapping(mapping.getTargetName(), modifier));
-                } else {
-                        mapper.mapFromObf(vc, entry, new EntryMapping(entry.getName(), modifier));
-                }
-
-                chp.invalidateMapped();
-        }
-
         public StructureTreeNode getClassStructure(ClassEntry entry, StructureTreeOptions options) {
                 StructureTreeNode rootNode = new StructureTreeNode(this.project, entry, entry);
                 rootNode.load(this.project, options);
@@ -471,74 +462,54 @@ public class GuiController implements ClientPacketHandler {
         }
 
         @Override
-        public void rename(ValidationContext vc, EntryReference<Entry<?>, Entry<?>> reference, String newName, boolean refreshClassTree) {
-                rename(vc, reference, newName, refreshClassTree, false);
-        }
-
-        public void rename(ValidationContext vc, EntryReference<Entry<?>, Entry<?>> reference, String newName, boolean refreshClassTree, boolean validateOnly) {
-                Entry<?> entry = reference.getNameableEntry();
-                EntryMapping previous = project.getMapper().getDeobfMapping(entry);
-                project.getMapper().mapFromObf(vc, entry, previous != null ? previous.withName(newName) : new EntryMapping(newName), true, validateOnly);
+        public boolean applyChangeFromServer(EntryChange<?> change) {
+                ValidationContext vc = new ValidationContext();
+                vc.setActiveElement(PrintValidatable.INSTANCE);
+                this.applyChange0(vc, change);
                 gui.showStructure(gui.getActiveEditor());
 
-                if (validateOnly || !vc.canProceed()) return;
+                return vc.canProceed();
+        }
 
-                if (refreshClassTree && reference.entry instanceof ClassEntry && !((ClassEntry) reference.entry).isInnerClass())
-                        this.gui.moveClassTree(reference.entry, newName);
+        public void validateChange(ValidationContext vc, EntryChange<?> change) {
+                if (change.getDeobfName().isSet()) {
+                        EntryValidation.validateRename(vc, this.project, change.getTarget(), change.getDeobfName().getNewValue());
+                }
 
-                chp.invalidateMapped();
+                if (change.getJavadoc().isSet()) {
+                        EntryValidation.validateJavadoc(vc, change.getJavadoc().getNewValue());
+                }
         }
 
-        @Override
-        public void removeMapping(ValidationContext vc, EntryReference<Entry<?>, Entry<?>> reference) {
-                project.getMapper().removeByObf(vc, reference.getNameableEntry());
+        public void applyChange(ValidationContext vc, EntryChange<?> change) {
+                this.applyChange0(vc, change);
                 gui.showStructure(gui.getActiveEditor());
-
                 if (!vc.canProceed()) return;
-
-                if (reference.entry instanceof ClassEntry)
-                        this.gui.moveClassTree(reference.entry, false, true);
-
-                chp.invalidateMapped();
+                this.sendPacket(new EntryChangeC2SPacket(change));
         }
 
-        @Override
-        public void changeDocs(ValidationContext vc, EntryReference<Entry<?>, Entry<?>> reference, String updatedDocs) {
-                changeDocs(vc, reference, updatedDocs, false);
-        }
-
-        public void changeDocs(ValidationContext vc, EntryReference<Entry<?>, Entry<?>> reference, String updatedDocs, boolean validateOnly) {
-                changeDoc(vc, reference.entry, updatedDocs, validateOnly);
-
-                if (validateOnly || !vc.canProceed()) return;
+        private void applyChange0(ValidationContext vc, EntryChange<?> change) {
+                validateChange(vc, change);
+                if (!vc.canProceed()) return;
 
-                chp.invalidateJavadoc(reference.getLocationClassEntry());
-        }
+                Entry<?> target = change.getTarget();
+                EntryMapping prev = this.project.getMapper().getDeobfMapping(target);
+                EntryMapping mapping = EntryUtil.applyChange(vc, this.project.getMapper(), change);
 
-        private void changeDoc(ValidationContext vc, Entry<?> obfEntry, String newDoc, boolean validateOnly) {
-                EntryRemapper mapper = project.getMapper();
+                boolean renamed = !change.getDeobfName().isUnchanged();
 
-                EntryMapping deobfMapping = mapper.getDeobfMapping(obfEntry);
-                if (deobfMapping == null) {
-                        deobfMapping = new EntryMapping(mapper.deobfuscate(obfEntry).getName());
+                if (renamed && target instanceof ClassEntry && !((ClassEntry) target).isInnerClass()) {
+                        this.gui.moveClassTree(target, prev.targetName() == null, mapping.targetName() == null);
                 }
 
-                mapper.mapFromObf(vc, obfEntry, deobfMapping.withDocs(newDoc), false, validateOnly);
-        }
+                if (!Objects.equals(prev.targetName(), mapping.targetName())) {
+                        this.chp.invalidateMapped();
+                }
 
-        @Override
-        public void markAsDeobfuscated(ValidationContext vc, EntryReference<Entry<?>, Entry<?>> reference) {
-                EntryRemapper mapper = project.getMapper();
-                Entry<?> entry = reference.getNameableEntry();
-                mapper.mapFromObf(vc, entry, new EntryMapping(mapper.deobfuscate(entry).getName()));
+                if (!Objects.equals(prev.javadoc(), mapping.javadoc())) {
+                        this.chp.invalidateJavadoc(target.getTopLevelClass());
+                }
                 gui.showStructure(gui.getActiveEditor());
-
-                if (!vc.canProceed()) return;
-
-                if (reference.entry instanceof ClassEntry && !((ClassEntry) reference.entry).isInnerClass())
-                        this.gui.moveClassTree(reference.entry, true, false);
-
-                chp.invalidateMapped();
         }
 
         public void openStats(Set<StatsMember> includedMembers, String topLevelPackage, boolean includeSynthetic) {
diff --git a/enigma-swing/src/main/java/cuchaz/enigma/gui/dialog/JavadocDialog.java b/enigma-swing/src/main/java/cuchaz/enigma/gui/dialog/JavadocDialog.java
index 2fc67476..9470e11c 100644
--- a/enigma-swing/src/main/java/cuchaz/enigma/gui/dialog/JavadocDialog.java
+++ b/enigma-swing/src/main/java/cuchaz/enigma/gui/dialog/JavadocDialog.java
@@ -29,23 +29,22 @@ import cuchaz.enigma.gui.config.UiConfig;
 import cuchaz.enigma.gui.elements.ValidatableTextArea;
 import cuchaz.enigma.gui.util.GuiUtil;
 import cuchaz.enigma.gui.util.ScaleUtil;
-import cuchaz.enigma.network.packet.ChangeDocsC2SPacket;
+import cuchaz.enigma.translation.mapping.EntryChange;
 import cuchaz.enigma.translation.representation.entry.Entry;
 import cuchaz.enigma.utils.I18n;
-import cuchaz.enigma.utils.validation.Message;
 import cuchaz.enigma.utils.validation.ValidationContext;
 
 public class JavadocDialog {
 
         private final JDialog ui;
         private final GuiController controller;
-        private final EntryReference<Entry<?>, Entry<?>> entry;
+        private final Entry<?> entry;
 
         private final ValidatableTextArea text;
 
         private final ValidationContext vc = new ValidationContext();
 
-        private JavadocDialog(JFrame parent, GuiController controller, EntryReference<Entry<?>, Entry<?>> entry, String preset) {
+        private JavadocDialog(JFrame parent, GuiController controller, Entry<?> entry, String preset) {
                 this.ui = new JDialog(parent, I18n.translate("javadocs.edit"));
                 this.controller = controller;
                 this.entry = entry;
@@ -161,28 +160,21 @@ public class JavadocDialog {
         public void validate() {
                 vc.setActiveElement(text);
 
-                if (text.getText().contains("*/")) {
-                        vc.raise(Message.ILLEGAL_DOC_COMMENT_END);
-                }
-
-                controller.changeDocs(vc, entry, text.getText(), true);
+                controller.validateChange(vc, EntryChange.modify(entry).withJavadoc(text.getText()));
         }
 
         public void save() {
                 vc.setActiveElement(text);
-                controller.changeDocs(vc, entry, text.getText().trim().isEmpty() ? null : text.getText());
-
-                if (!vc.canProceed()) return;
 
-                controller.sendPacket(new ChangeDocsC2SPacket(entry.getNameableEntry(), text.getText()));
+                controller.applyChange(vc, EntryChange.modify(entry).withJavadoc(text.getText()));
         }
 
         public static void show(JFrame parent, GuiController controller, EntryReference<Entry<?>, Entry<?>> entry) {
                 EntryReference<Entry<?>, Entry<?>> translatedReference = controller.project.getMapper().deobfuscate(entry);
                 String text = Strings.nullToEmpty(translatedReference.entry.getJavadocs());
 
-                JavadocDialog dialog = new JavadocDialog(parent, controller, entry, text);
-                dialog.ui.doLayout();
+                JavadocDialog dialog = new JavadocDialog(parent, controller, entry.getNameableEntry(), text);
+                //dialog.ui.doLayout();
                 dialog.ui.setVisible(true);
                 dialog.text.grabFocus();
         }
diff --git a/enigma-swing/src/main/java/cuchaz/enigma/gui/newabstraction/EntryValidation.java b/enigma-swing/src/main/java/cuchaz/enigma/gui/newabstraction/EntryValidation.java
new file mode 100644
index 00000000..898529a4
--- /dev/null
+++ b/enigma-swing/src/main/java/cuchaz/enigma/gui/newabstraction/EntryValidation.java
@@ -0,0 +1,22 @@
+package cuchaz.enigma.gui.newabstraction;
+
+import cuchaz.enigma.EnigmaProject;
+import cuchaz.enigma.translation.representation.entry.Entry;
+import cuchaz.enigma.utils.validation.Message;
+import cuchaz.enigma.utils.validation.ValidationContext;
+
+public class EntryValidation {
+
+        public static boolean validateJavadoc(ValidationContext vc, String javadoc) {
+                if (javadoc.contains("*/")) {
+                        vc.raise(Message.ILLEGAL_DOC_COMMENT_END);
+                        return false;
+                }
+                return true;
+        }
+
+        public static boolean validateRename(ValidationContext vc, EnigmaProject p, Entry<?> entry, String newName) {
+                return p.getMapper().getValidator().validateRename(vc, entry, newName);
+        }
+
+}
diff --git a/enigma-swing/src/main/java/cuchaz/enigma/gui/panels/DeobfPanel.java b/enigma-swing/src/main/java/cuchaz/enigma/gui/panels/DeobfPanel.java
index 5b7882b0..cd09c1a1 100644
--- a/enigma-swing/src/main/java/cuchaz/enigma/gui/panels/DeobfPanel.java
+++ b/enigma-swing/src/main/java/cuchaz/enigma/gui/panels/DeobfPanel.java
@@ -22,7 +22,7 @@ public class DeobfPanel extends JPanel {
 
                 this.deobfClasses = new ClassSelector(gui, ClassSelector.DEOBF_CLASS_COMPARATOR, true);
                 this.deobfClasses.setSelectionListener(gui.getController()::navigateTo);
-                this.deobfClasses.setRenameSelectionListener(gui::onPanelRename);
+                this.deobfClasses.setRenameSelectionListener(gui::onRenameFromClassTree);
 
                 this.setLayout(new BorderLayout());
                 this.add(this.title, BorderLayout.NORTH);
diff --git a/enigma-swing/src/main/java/cuchaz/enigma/gui/panels/IdentifierPanel.java b/enigma-swing/src/main/java/cuchaz/enigma/gui/panels/IdentifierPanel.java
index 3bae94c3..4ae0b7be 100644
--- a/enigma-swing/src/main/java/cuchaz/enigma/gui/panels/IdentifierPanel.java
+++ b/enigma-swing/src/main/java/cuchaz/enigma/gui/panels/IdentifierPanel.java
@@ -15,7 +15,6 @@ import javax.swing.JLabel;
 import javax.swing.JPanel;
 
 import cuchaz.enigma.EnigmaProject;
-import cuchaz.enigma.analysis.EntryReference;
 import cuchaz.enigma.gui.EditableType;
 import cuchaz.enigma.gui.Gui;
 import cuchaz.enigma.gui.elements.ConvertingTextField;
@@ -23,8 +22,8 @@ import cuchaz.enigma.gui.events.ConvertingTextFieldListener;
 import cuchaz.enigma.gui.util.GridBagConstraintsBuilder;
 import cuchaz.enigma.gui.util.GuiUtil;
 import cuchaz.enigma.gui.util.ScaleUtil;
-import cuchaz.enigma.network.packet.RenameC2SPacket;
 import cuchaz.enigma.translation.mapping.AccessModifier;
+import cuchaz.enigma.translation.mapping.EntryChange;
 import cuchaz.enigma.translation.mapping.EntryMapping;
 import cuchaz.enigma.translation.representation.entry.*;
 import cuchaz.enigma.utils.I18n;
@@ -76,7 +75,7 @@ public class IdentifierPanel {
         }
 
         private void onModifierChanged(AccessModifier modifier) {
-                gui.validateImmediateAction(vc -> this.gui.getController().onModifierChanged(vc, entry, modifier));
+                gui.validateImmediateAction(vc -> this.gui.getController().applyChange(vc, EntryChange.modify(entry).withAccess(modifier)));
         }
 
         public void refreshReference() {
@@ -176,13 +175,12 @@ public class IdentifierPanel {
         }
 
         private void validateRename(String newName) {
-                gui.getController().rename(vc, new EntryReference<>(entry, deobfEntry.getName()), newName, true, true);
+                gui.getController().validateChange(vc, EntryChange.modify(entry).withDeobfName(newName));
         }
 
         private void doRename(String newName) {
-                gui.getController().rename(vc, new EntryReference<>(entry, deobfEntry.getName()), newName, true);
-                if (!vc.canProceed()) return;
-                gui.getController().sendPacket(new RenameC2SPacket(entry, newName, true));
+                EntryChange<? extends Entry<?>> change = EntryChange.modify(entry).withDeobfName(newName);
+                gui.getController().applyChange(vc, change);
         }
 
         public void retranslateUi() {
@@ -277,12 +275,7 @@ public class IdentifierPanel {
 
                         JComboBox<AccessModifier> combo = new JComboBox<>(AccessModifier.values());
                         EntryMapping mapping = project.getMapper().getDeobfMapping(e);
-
-                        if (mapping != null) {
-                                combo.setSelectedIndex(mapping.getAccessModifier().ordinal());
-                        } else {
-                                combo.setSelectedIndex(AccessModifier.UNCHANGED.ordinal());
-                        }
+                        combo.setSelectedIndex(mapping.accessModifier().ordinal());
 
                         if (this.gui.isEditable(type)) {
                                 combo.addItemListener(event -> {
diff --git a/enigma-swing/src/main/java/cuchaz/enigma/gui/panels/ObfPanel.java b/enigma-swing/src/main/java/cuchaz/enigma/gui/panels/ObfPanel.java
index b384968d..7783843d 100644
--- a/enigma-swing/src/main/java/cuchaz/enigma/gui/panels/ObfPanel.java
+++ b/enigma-swing/src/main/java/cuchaz/enigma/gui/panels/ObfPanel.java
@@ -33,7 +33,7 @@ public class ObfPanel extends JPanel {
 
                 this.obfClasses = new ClassSelector(gui, obfClassComparator, false);
                 this.obfClasses.setSelectionListener(gui.getController()::navigateTo);
-                this.obfClasses.setRenameSelectionListener(gui::onPanelRename);
+                this.obfClasses.setRenameSelectionListener(gui::onRenameFromClassTree);
 
                 this.setLayout(new BorderLayout());
                 this.add(this.title, BorderLayout.NORTH);
diff --git a/enigma/src/main/java/cuchaz/enigma/source/DecompiledClassSource.java b/enigma/src/main/java/cuchaz/enigma/source/DecompiledClassSource.java
index 9ac611f5..5f371a58 100644
--- a/enigma/src/main/java/cuchaz/enigma/source/DecompiledClassSource.java
+++ b/enigma/src/main/java/cuchaz/enigma/source/DecompiledClassSource.java
@@ -79,7 +79,7 @@ public class DecompiledClassSource {
                 return null;
         }
 
-        private Optional<String> proposeName(EnigmaProject project, Entry<?> entry) {
+        public static Optional<String> proposeName(EnigmaProject project, Entry<?> entry) {
                 EnigmaServices services = project.getEnigma().getServices();
 
                 return services.get(NameProposalService.TYPE).stream().flatMap(nameProposalService -> {
diff --git a/enigma/src/main/java/cuchaz/enigma/source/cfr/EnigmaDumper.java b/enigma/src/main/java/cuchaz/enigma/source/cfr/EnigmaDumper.java
index b85851fa..4e8940ad 100644
--- a/enigma/src/main/java/cuchaz/enigma/source/cfr/EnigmaDumper.java
+++ b/enigma/src/main/java/cuchaz/enigma/source/cfr/EnigmaDumper.java
@@ -148,7 +148,7 @@ public class EnigmaDumper extends StringStreamDumper {
                         continue;
                     }
 
-                    String javaDoc = mapping.getJavadoc();
+                    String javaDoc = mapping.javadoc();
                     if (javaDoc != null) {
                         recordComponentDocs.add(String.format("@param %s %s", field.getFieldName(), javaDoc));
                     }
@@ -159,7 +159,7 @@ public class EnigmaDumper extends StringStreamDumper {
 
             String javadoc = null;
             if (mapping != null) {
-                javadoc = mapping.getJavadoc();
+                javadoc = mapping.javadoc();
             }
 
             if (javadoc != null || !recordComponentDocs.isEmpty()) {
@@ -191,7 +191,7 @@ public class EnigmaDumper extends StringStreamDumper {
             MethodEntry methodEntry = getMethodEntry(method);
             EntryMapping mapping = mapper.getDeobfMapping(methodEntry);
             if (mapping != null) {
-                String javadoc = mapping.getJavadoc();
+                String javadoc = mapping.javadoc();
                 if (javadoc != null) {
                     lines.addAll(Arrays.asList(javadoc.split("\\R")));
                 }
@@ -204,9 +204,9 @@ public class EnigmaDumper extends StringStreamDumper {
                     if (each instanceof LocalVariableEntry) {
                         EntryMapping paramMapping = mapper.getDeobfMapping(each);
                         if (paramMapping != null) {
-                            String javadoc = paramMapping.getJavadoc();
+                            String javadoc = paramMapping.javadoc();
                             if (javadoc != null) {
-                                lines.addAll(Arrays.asList(("@param " + paramMapping.getTargetName() + " " + javadoc).split("\\R")));
+                                lines.addAll(Arrays.asList(("@param " + paramMapping.targetName() + " " + javadoc).split("\\R")));
                             }
                         }
                     }
@@ -230,7 +230,7 @@ public class EnigmaDumper extends StringStreamDumper {
         if (mapper != null && !recordComponent) {
             EntryMapping mapping = mapper.getDeobfMapping(getFieldEntry(owner, field.getFieldName(), field.getDescriptor()));
             if (mapping != null) {
-                String javadoc = mapping.getJavadoc();
+                String javadoc = mapping.javadoc();
                 if (javadoc != null) {
                     print("/**").newln();
                     for (String line : javadoc.split("\\R")) {
diff --git a/enigma/src/main/java/cuchaz/enigma/source/procyon/transformers/AddJavadocsAstTransform.java b/enigma/src/main/java/cuchaz/enigma/source/procyon/transformers/AddJavadocsAstTransform.java
index 70fc8c6b..1e5beb1e 100644
--- a/enigma/src/main/java/cuchaz/enigma/source/procyon/transformers/AddJavadocsAstTransform.java
+++ b/enigma/src/main/java/cuchaz/enigma/source/procyon/transformers/AddJavadocsAstTransform.java
@@ -47,16 +47,17 @@ public final class AddJavadocsAstTransform implements IAstTransform {
 
                 private <T extends AstNode> Comment[] getComments(T node, Function<T, Entry<?>> retriever) {
                         final EntryMapping mapping = remapper.getDeobfMapping(retriever.apply(node));
-                        final String docs = mapping == null ? null : Strings.emptyToNull(mapping.getJavadoc());
+                        final String docs = Strings.emptyToNull(mapping.javadoc());
                         return docs == null ? null : Stream.of(docs.split("\\R")).map(st -> new Comment(st,
                                         CommentType.Documentation)).toArray(Comment[]::new);
                 }
 
                 private Comment[] getParameterComments(ParameterDeclaration node, Function<ParameterDeclaration, Entry<?>> retriever) {
-                        final EntryMapping mapping = remapper.getDeobfMapping(retriever.apply(node));
+                        Entry<?> entry = retriever.apply(node);
+                        final EntryMapping mapping = remapper.getDeobfMapping(entry);
                         final Comment[] ret = getComments(node, retriever);
                         if (ret != null) {
-                                final String paramPrefix = "@param " + mapping.getTargetName() + " ";
+                                final String paramPrefix = "@param " + (mapping.targetName() != null ? mapping.targetName() : entry.getName()) + " ";
                                 final String indent = Strings.repeat(" ", paramPrefix.length());
                                 ret[0].setContent(paramPrefix + ret[0].getContent());
                                 for (int i = 1; i < ret.length; i++) {
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryChange.java b/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryChange.java
new file mode 100644
index 00000000..b5ec8552
--- /dev/null
+++ b/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryChange.java
@@ -0,0 +1,97 @@
+package cuchaz.enigma.translation.mapping;
+
+import java.util.Objects;
+import java.util.Optional;
+
+import javax.annotation.Nullable;
+
+import cuchaz.enigma.EnigmaProject;
+import cuchaz.enigma.source.DecompiledClassSource;
+import cuchaz.enigma.translation.representation.entry.Entry;
+import cuchaz.enigma.utils.TristateChange;
+
+public final class EntryChange<E extends Entry<?>> {
+
+        private final E target;
+        private final TristateChange<String> deobfName;
+        private final TristateChange<String> javadoc;
+        private final TristateChange<AccessModifier> access;
+
+        private EntryChange(E target, TristateChange<String> deobfName, TristateChange<String> javadoc, TristateChange<AccessModifier> access) {
+                this.target = target;
+                this.deobfName = deobfName;
+                this.javadoc = javadoc;
+                this.access = access;
+        }
+
+        public static <E extends Entry<?>> EntryChange<E> modify(E target) {
+                return new EntryChange<>(target, TristateChange.unchanged(), TristateChange.unchanged(), TristateChange.unchanged());
+        }
+
+        public EntryChange<E> withDeobfName(String name) {
+                return new EntryChange<>(this.target, TristateChange.set(name), this.javadoc, this.access);
+        }
+
+        public EntryChange<E> withDefaultDeobfName(@Nullable EnigmaProject project) {
+                Optional<String> proposed = project != null ? DecompiledClassSource.proposeName(project, this.target) : Optional.empty();
+                return this.withDeobfName(proposed.orElse(this.target.getName()));
+        }
+
+        public EntryChange<E> clearDeobfName() {
+                return new EntryChange<>(this.target, TristateChange.reset(), this.javadoc, this.access);
+        }
+
+        public EntryChange<E> withJavadoc(String javadoc) {
+                return new EntryChange<>(this.target, this.deobfName, TristateChange.set(javadoc), this.access);
+        }
+
+        public EntryChange<E> clearJavadoc() {
+                return new EntryChange<>(this.target, this.deobfName, TristateChange.reset(), this.access);
+        }
+
+        public EntryChange<E> withAccess(AccessModifier access) {
+                return new EntryChange<>(this.target, this.deobfName, this.javadoc, TristateChange.set(access));
+        }
+
+        public EntryChange<E> clearAccess() {
+                return new EntryChange<>(this.target, this.deobfName, this.javadoc, TristateChange.reset());
+        }
+
+        public TristateChange<String> getDeobfName() {
+                return this.deobfName;
+        }
+
+        public TristateChange<String> getJavadoc() {
+                return this.javadoc;
+        }
+
+        public TristateChange<AccessModifier> getAccess() {
+                return this.access;
+        }
+
+        public E getTarget() {
+                return this.target;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (!(o instanceof EntryChange)) return false;
+                EntryChange<?> that = (EntryChange<?>) o;
+                return Objects.equals(this.target, that.target) &&
+                                Objects.equals(this.deobfName, that.deobfName) &&
+                                Objects.equals(this.javadoc, that.javadoc) &&
+                                Objects.equals(this.access, that.access);
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(this.target, this.deobfName, this.javadoc, this.access);
+        }
+
+        @Override
+        public String toString() {
+                return String.format("EntryChange { target: %s, deobfName: %s, javadoc: %s, access: %s }", this.target, this.deobfName, this.javadoc, this.access);
+        }
+
+}
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryMapping.java b/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryMapping.java
index c607817c..e916bf35 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryMapping.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryMapping.java
@@ -1,49 +1,37 @@
 package cuchaz.enigma.translation.mapping;
 
+import java.util.Arrays;
+
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
-public class EntryMapping {
-        private final String targetName;
-        private final AccessModifier accessModifier;
-        private final @Nullable String javadoc;
+public record EntryMapping(
+                @Nullable String targetName,
+                @Nonnull AccessModifier accessModifier,
+                @Nullable String javadoc
+) {
+        public static final EntryMapping DEFAULT = new EntryMapping(null, AccessModifier.UNCHANGED, null);
+
+        public EntryMapping {
+                if (accessModifier == null) {
+                        accessModifier = AccessModifier.UNCHANGED;
+                        System.err.println("EntryMapping initialized with 'null' accessModifier, assuming UNCHANGED. Please fix.");
+                        Arrays.stream(new Exception().getStackTrace()).skip(1).map("\tat %s"::formatted).forEach(System.err::println);
+                }
+        }
 
-        public EntryMapping(@Nonnull String targetName) {
+        public EntryMapping(@Nullable String targetName) {
                 this(targetName, AccessModifier.UNCHANGED);
         }
 
-        public EntryMapping(@Nonnull String targetName, @Nullable String javadoc) {
+        public EntryMapping(@Nullable String targetName, @Nullable String javadoc) {
                 this(targetName, AccessModifier.UNCHANGED, javadoc);
         }
 
-        public EntryMapping(@Nonnull String targetName, AccessModifier accessModifier) {
+        public EntryMapping(@Nullable String targetName, AccessModifier accessModifier) {
                 this(targetName, accessModifier, null);
         }
 
-        public EntryMapping(@Nonnull String targetName, AccessModifier accessModifier, @Nullable String javadoc) {
-                this.targetName = targetName;
-                this.accessModifier = accessModifier;
-                this.javadoc = javadoc;
-        }
-
-        @Nonnull
-        public String getTargetName() {
-                return targetName;
-        }
-
-        @Nonnull
-        public AccessModifier getAccessModifier() {
-                if (accessModifier == null) {
-                        return AccessModifier.UNCHANGED;
-                }
-                return accessModifier;
-        }
-
-        @Nullable
-        public String getJavadoc() {
-                return javadoc;
-        }
-
         public EntryMapping withName(String newName) {
                 return new EntryMapping(newName, accessModifier, javadoc);
         }
@@ -55,21 +43,4 @@ public class EntryMapping {
         public EntryMapping withDocs(String newDocs) {
                 return new EntryMapping(targetName, accessModifier, newDocs);
         }
-
-        @Override
-        public boolean equals(Object obj) {
-                if (obj == this) return true;
-
-                if (obj instanceof EntryMapping) {
-                        EntryMapping mapping = (EntryMapping) obj;
-                        return mapping.targetName.equals(targetName) && mapping.accessModifier.equals(accessModifier);
-                }
-
-                return false;
-        }
-
-        @Override
-        public int hashCode() {
-                return targetName.hashCode() + accessModifier.hashCode() * 31;
-        }
 }
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryRemapper.java b/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryRemapper.java
index 8b5490e1..0977b742 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryRemapper.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryRemapper.java
@@ -1,10 +1,11 @@
 package cuchaz.enigma.translation.mapping;
 
 import java.util.Collection;
+import java.util.Objects;
 import java.util.List;
 import java.util.stream.Stream;
 
-import javax.annotation.Nullable;
+import javax.annotation.Nonnull;
 
 import cuchaz.enigma.analysis.index.JarIndex;
 import cuchaz.enigma.translation.MappingTranslator;
@@ -50,15 +51,15 @@ public class EntryRemapper {
                 return new EntryRemapper(index, new HashEntryTree<>());
         }
 
-        public <E extends Entry<?>> void mapFromObf(ValidationContext vc, E obfuscatedEntry, @Nullable EntryMapping deobfMapping) {
-                mapFromObf(vc, obfuscatedEntry, deobfMapping, true);
+        public void validatePutMapping(ValidationContext vc, Entry<?> obfuscatedEntry, @Nonnull EntryMapping deobfMapping) {
+                doPutMapping(vc, obfuscatedEntry, deobfMapping, true);
         }
 
-        public <E extends Entry<?>> void mapFromObf(ValidationContext vc, E obfuscatedEntry, @Nullable EntryMapping deobfMapping, boolean renaming) {
-                mapFromObf(vc, obfuscatedEntry, deobfMapping, renaming, false);
+        public void putMapping(ValidationContext vc, Entry<?> obfuscatedEntry, @Nonnull EntryMapping deobfMapping) {
+                doPutMapping(vc, obfuscatedEntry, deobfMapping, false);
         }
 
-        public <E extends Entry<?>> void mapFromObf(ValidationContext vc, E obfuscatedEntry, @Nullable EntryMapping deobfMapping, boolean renaming, boolean validateOnly) {
+        private void doPutMapping(ValidationContext vc, Entry<?> obfuscatedEntry, @Nonnull EntryMapping deobfMapping, boolean validateOnly) {
                 if (obfuscatedEntry instanceof FieldEntry) {
                         FieldEntry fieldEntry = (FieldEntry) obfuscatedEntry;
                         ClassEntry classEntry = fieldEntry.getParent();
@@ -66,25 +67,27 @@ public class EntryRemapper {
                         mapRecordComponentGetter(vc, classEntry, fieldEntry, deobfMapping);
                 }
 
-                Collection<E> resolvedEntries = obfResolver.resolveEntry(obfuscatedEntry, renaming ? ResolutionStrategy.RESOLVE_ROOT : ResolutionStrategy.RESOLVE_CLOSEST);
+                boolean renaming = !Objects.equals(getDeobfMapping(obfuscatedEntry).targetName(), deobfMapping.targetName());
 
-                if (renaming && deobfMapping != null) {
-                        for (E resolvedEntry : resolvedEntries) {
-                                validator.validateRename(vc, resolvedEntry, deobfMapping.getTargetName());
+                Collection<Entry<?>> resolvedEntries = obfResolver.resolveEntry(obfuscatedEntry, renaming ? ResolutionStrategy.RESOLVE_ROOT : ResolutionStrategy.RESOLVE_CLOSEST);
+
+                if (renaming && deobfMapping.targetName() != null) {
+                        for (Entry<?> resolvedEntry : resolvedEntries) {
+                                validator.validateRename(vc, resolvedEntry, deobfMapping.targetName());
                         }
                 }
 
                 if (validateOnly || !vc.canProceed()) return;
 
-                for (E resolvedEntry : resolvedEntries) {
-                        obfToDeobf.insert(resolvedEntry, deobfMapping);
+                for (Entry<?> resolvedEntry : resolvedEntries) {
+                        if (deobfMapping.equals(EntryMapping.DEFAULT)) {
+                                obfToDeobf.insert(resolvedEntry, null);
+                        } else {
+                                obfToDeobf.insert(resolvedEntry, deobfMapping);
+                        }
                 }
         }
 
-        public void removeByObf(ValidationContext vc, Entry<?> obfuscatedEntry) {
-                mapFromObf(vc, obfuscatedEntry, null);
-        }
-
         // A little bit of a hack to also map the getter method for record fields/components.
         private void mapRecordComponentGetter(ValidationContext vc, ClassEntry classEntry, FieldEntry fieldEntry, EntryMapping fieldMapping) {
                 if (!jarIndex.getEntryIndex().getClassAccess(classEntry).isRecord() || jarIndex.getEntryIndex().getFieldAccess(fieldEntry).isStatic()) {
@@ -107,20 +110,17 @@ public class EntryRemapper {
                 }
 
                 if (methodEntry == null && fieldMapping != null) {
-                        vc.raise(Message.UNKNOWN_RECORD_GETTER, fieldMapping.getTargetName());
+                        vc.raise(Message.UNKNOWN_RECORD_GETTER, fieldMapping.targetName());
                         return;
                 }
 
-                mapFromObf(vc, methodEntry, fieldMapping != null ? new EntryMapping(fieldMapping.getTargetName()) : null);
+                putMapping(vc, methodEntry, fieldMapping != null ? new EntryMapping(fieldMapping.targetName()) : null);
         }
 
-        @Nullable
+        @Nonnull
         public EntryMapping getDeobfMapping(Entry<?> entry) {
-                return obfToDeobf.get(entry);
-        }
-
-        public boolean hasDeobfMapping(Entry<?> obfEntry) {
-                return obfToDeobf.contains(obfEntry);
+                EntryMapping entryMapping = obfToDeobf.get(entry);
+                return entryMapping == null ? EntryMapping.DEFAULT : entryMapping;
         }
 
         public <T extends Translatable> TranslateResult<T> extendedDeobfuscate(T translatable) {
@@ -158,4 +158,9 @@ public class EntryRemapper {
         public EntryResolver getObfResolver() {
                 return obfResolver;
         }
+
+        public MappingValidator getValidator() {
+                return validator;
+        }
+
 }
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryUtil.java b/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryUtil.java
new file mode 100644
index 00000000..582076c1
--- /dev/null
+++ b/enigma/src/main/java/cuchaz/enigma/translation/mapping/EntryUtil.java
@@ -0,0 +1,42 @@
+package cuchaz.enigma.translation.mapping;
+
+import javax.annotation.Nonnull;
+
+import cuchaz.enigma.translation.representation.entry.Entry;
+import cuchaz.enigma.utils.validation.ValidationContext;
+
+public class EntryUtil {
+
+        public static EntryMapping applyChange(ValidationContext vc, EntryRemapper remapper, EntryChange<?> change) {
+                Entry<?> target = change.getTarget();
+                EntryMapping prev = remapper.getDeobfMapping(target);
+                EntryMapping mapping = EntryUtil.applyChange(prev, change);
+
+                remapper.putMapping(vc, target, mapping);
+
+                return mapping;
+        }
+
+        public static EntryMapping applyChange(@Nonnull EntryMapping self, EntryChange<?> change) {
+                if (change.getDeobfName().isSet()) {
+                        self = self.withName(change.getDeobfName().getNewValue());
+                } else if (change.getDeobfName().isReset()) {
+                        self = self.withName(null);
+                }
+
+                if (change.getJavadoc().isSet()) {
+                        self = self.withDocs(change.getJavadoc().getNewValue());
+                } else if (change.getJavadoc().isReset()) {
+                        self = self.withDocs(null);
+                }
+
+                if (change.getAccess().isSet()) {
+                        self = self.withModifier(change.getAccess().getNewValue());
+                } else if (change.getAccess().isReset()) {
+                        self = self.withModifier(AccessModifier.UNCHANGED);
+                }
+
+                return self;
+        }
+
+}
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/mapping/MappingValidator.java b/enigma/src/main/java/cuchaz/enigma/translation/mapping/MappingValidator.java
index 1615912b..065e5c3e 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/mapping/MappingValidator.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/mapping/MappingValidator.java
@@ -25,18 +25,22 @@ public class MappingValidator {
                 this.index = index;
         }
 
-        public void validateRename(ValidationContext vc, Entry<?> entry, String name) {
+        public boolean validateRename(ValidationContext vc, Entry<?> entry, String name) {
                 Collection<Entry<?>> equivalentEntries = index.getEntryResolver().resolveEquivalentEntries(entry);
+                boolean error = false;
                 for (Entry<?> equivalentEntry : equivalentEntries) {
                         equivalentEntry.validateName(vc, name);
-                        validateUnique(vc, equivalentEntry, name);
+                        error |= validateUnique(vc, equivalentEntry, name);
                 }
+                return error;
         }
 
-        private void validateUnique(ValidationContext vc, Entry<?> entry, String name) {
+        private boolean validateUnique(ValidationContext vc, Entry<?> entry, String name) {
                 ClassEntry containingClass = entry.getContainingClass();
                 Collection<ClassEntry> relatedClasses = getRelatedClasses(containingClass);
 
+                boolean error = false;
+
                 for (ClassEntry relatedClass : relatedClasses) {
                         Entry<?> relatedEntry = entry.replaceAncestor(containingClass, relatedClass);
                         Entry<?> translatedEntry = deobfuscator.translate(relatedEntry);
@@ -52,8 +56,11 @@ public class MappingValidator {
                                 } else {
                                         vc.raise(Message.NONUNIQUE_NAME, name);
                                 }
+                                error = true;
                         }
                 }
+
+                return error;
         }
 
         private Collection<ClassEntry> getRelatedClasses(ClassEntry classEntry) {
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/mapping/MappingsChecker.java b/enigma/src/main/java/cuchaz/enigma/translation/mapping/MappingsChecker.java
index 141a07cc..392b1a67 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/mapping/MappingsChecker.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/mapping/MappingsChecker.java
@@ -75,7 +75,7 @@ public class MappingsChecker {
                 private final Map<Entry<?>, String> droppedMappings = new HashMap<>();
 
                 public void drop(Entry<?> entry, EntryMapping mapping) {
-                        droppedMappings.put(entry, mapping.getTargetName());
+                        droppedMappings.put(entry, mapping.targetName() != null ? mapping.targetName() : entry.getName());
                 }
 
                 void apply(EntryTree<EntryMapping> mappings) {
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/RawEntryMapping.java b/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/RawEntryMapping.java
index 79587a0b..6465008b 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/RawEntryMapping.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/RawEntryMapping.java
@@ -1,23 +1,23 @@
 package cuchaz.enigma.translation.mapping.serde;
 
-import cuchaz.enigma.translation.mapping.AccessModifier;
-import cuchaz.enigma.translation.mapping.EntryMapping;
-
 import java.util.ArrayList;
 import java.util.List;
 
+import cuchaz.enigma.translation.mapping.AccessModifier;
+import cuchaz.enigma.translation.mapping.EntryMapping;
+
 public final class RawEntryMapping {
         private final String targetName;
         private final AccessModifier access;
-        private List<String> javadocs = new ArrayList<>();
+        private final List<String> javadocs = new ArrayList<>();
 
         public RawEntryMapping(String targetName) {
-                this(targetName, null);
+                this(targetName, AccessModifier.UNCHANGED);
         }
 
         public RawEntryMapping(String targetName, AccessModifier access) {
                 this.access = access;
-                this.targetName = targetName;
+                this.targetName = targetName != null && !targetName.equals("-") ? targetName : null;
         }
 
         public void addJavadocLine(String line) {
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/enigma/EnigmaMappingsReader.java b/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/enigma/EnigmaMappingsReader.java
index 27545c03..ccc25dff 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/enigma/EnigmaMappingsReader.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/enigma/EnigmaMappingsReader.java
@@ -1,15 +1,21 @@
 package cuchaz.enigma.translation.mapping.serde.enigma;
 
+import java.io.IOException;
+import java.nio.file.FileSystem;
+import java.nio.file.FileSystems;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.*;
+
+import javax.annotation.Nullable;
+
 import com.google.common.base.Charsets;
+
 import cuchaz.enigma.ProgressListener;
-import cuchaz.enigma.translation.mapping.serde.MappingParseException;
 import cuchaz.enigma.translation.mapping.AccessModifier;
 import cuchaz.enigma.translation.mapping.EntryMapping;
 import cuchaz.enigma.translation.mapping.MappingPair;
-import cuchaz.enigma.translation.mapping.serde.MappingSaveParameters;
-import cuchaz.enigma.translation.mapping.serde.MappingHelper;
-import cuchaz.enigma.translation.mapping.serde.MappingsReader;
-import cuchaz.enigma.translation.mapping.serde.RawEntryMapping;
+import cuchaz.enigma.translation.mapping.serde.*;
 import cuchaz.enigma.translation.mapping.tree.EntryTree;
 import cuchaz.enigma.translation.mapping.tree.HashEntryTree;
 import cuchaz.enigma.translation.representation.MethodDescriptor;
@@ -17,18 +23,6 @@ import cuchaz.enigma.translation.representation.TypeDescriptor;
 import cuchaz.enigma.translation.representation.entry.*;
 import cuchaz.enigma.utils.I18n;
 
-import javax.annotation.Nullable;
-import java.io.IOException;
-import java.nio.file.FileSystem;
-import java.nio.file.FileSystems;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.util.ArrayDeque;
-import java.util.Arrays;
-import java.util.Deque;
-import java.util.List;
-import java.util.Locale;
-
 public enum EnigmaMappingsReader implements MappingsReader {
         FILE {
                 @Override
@@ -200,12 +194,12 @@ public enum EnigmaMappingsReader implements MappingsReader {
                                 throw new RuntimeException("Unknown token '" + keyToken + "'");
                 }
         }
-        
+
         private static void readJavadoc(MappingPair<?, RawEntryMapping> parent, String[] tokens) {
                 if (parent == null)
                         throw new IllegalStateException("Javadoc has no parent!");
                 // Empty string to concat
-                String jdLine = tokens.length > 1 ? String.join(" ", Arrays.copyOfRange(tokens,1,tokens.length))  : "";
+                String jdLine = tokens.length > 1 ? String.join(" ", Arrays.copyOfRange(tokens, 1, tokens.length)) : "";
                 if (parent.getMapping() == null) {
                         parent.setMapping(new RawEntryMapping(parent.getEntry().getName(), AccessModifier.UNCHANGED));
                 }
@@ -237,11 +231,7 @@ public enum EnigmaMappingsReader implements MappingsReader {
                         modifier = parseModifier(tokens[3]);
                 }
 
-                if (mapping != null) {
-                        return new MappingPair<>(obfuscatedEntry, new RawEntryMapping(mapping, modifier));
-                } else {
-                        return new MappingPair<>(obfuscatedEntry);
-                }
+                return new MappingPair<>(obfuscatedEntry, new RawEntryMapping(mapping, modifier));
         }
 
         private static MappingPair<FieldEntry, RawEntryMapping> parseField(@Nullable Entry<?> parent, String[] tokens) {
@@ -252,7 +242,7 @@ public enum EnigmaMappingsReader implements MappingsReader {
                 ClassEntry ownerEntry = (ClassEntry) parent;
 
                 String obfuscatedName = tokens[1];
-                String mapping = obfuscatedName;
+                String mapping = null;
                 AccessModifier modifier = AccessModifier.UNCHANGED;
                 TypeDescriptor descriptor;
 
@@ -269,19 +259,15 @@ public enum EnigmaMappingsReader implements MappingsReader {
                                 descriptor = new TypeDescriptor(tokens[3]);
                         }
                 } else if (tokens.length == 5) {
-                        descriptor = new TypeDescriptor(tokens[3]);
                         mapping = tokens[2];
-                        modifier = parseModifier(tokens[4]);
+                        modifier = parseModifier(tokens[3]);
+                        descriptor = new TypeDescriptor(tokens[4]);
                 } else {
                         throw new RuntimeException("Invalid field declaration");
                 }
 
                 FieldEntry obfuscatedEntry = new FieldEntry(ownerEntry, obfuscatedName, descriptor);
-                if (mapping != null) {
-                        return new MappingPair<>(obfuscatedEntry, new RawEntryMapping(mapping, modifier));
-                } else {
-                        return new MappingPair<>(obfuscatedEntry);
-                }
+                return new MappingPair<>(obfuscatedEntry, new RawEntryMapping(mapping, modifier));
         }
 
         private static MappingPair<MethodEntry, RawEntryMapping> parseMethod(@Nullable Entry<?> parent, String[] tokens) {
@@ -317,11 +303,7 @@ public enum EnigmaMappingsReader implements MappingsReader {
                 }
 
                 MethodEntry obfuscatedEntry = new MethodEntry(ownerEntry, obfuscatedName, descriptor);
-                if (mapping != null) {
-                        return new MappingPair<>(obfuscatedEntry, new RawEntryMapping(mapping, modifier));
-                } else {
-                        return new MappingPair<>(obfuscatedEntry);
-                }
+                return new MappingPair<>(obfuscatedEntry, new RawEntryMapping(mapping, modifier));
         }
 
         private static MappingPair<LocalVariableEntry, RawEntryMapping> parseArgument(@Nullable Entry<?> parent, String[] tokens) {
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/enigma/EnigmaMappingsWriter.java b/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/enigma/EnigmaMappingsWriter.java
index d9f1470d..5d7a7893 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/enigma/EnigmaMappingsWriter.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/enigma/EnigmaMappingsWriter.java
@@ -15,12 +15,7 @@ import java.io.IOException;
 import java.io.PrintWriter;
 import java.net.URI;
 import java.net.URISyntaxException;
-import java.nio.file.DirectoryStream;
-import java.nio.file.FileSystem;
-import java.nio.file.FileSystems;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.nio.file.Paths;
+import java.nio.file.*;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -28,25 +23,19 @@ import java.util.Objects;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.stream.Stream;
 
+import javax.annotation.Nonnull;
+
 import cuchaz.enigma.ProgressListener;
 import cuchaz.enigma.translation.MappingTranslator;
 import cuchaz.enigma.translation.Translator;
 import cuchaz.enigma.translation.mapping.AccessModifier;
 import cuchaz.enigma.translation.mapping.EntryMapping;
 import cuchaz.enigma.translation.mapping.MappingDelta;
-import cuchaz.enigma.translation.mapping.serde.MappingFileNameFormat;
-import cuchaz.enigma.translation.mapping.serde.MappingSaveParameters;
 import cuchaz.enigma.translation.mapping.VoidEntryResolver;
-import cuchaz.enigma.translation.mapping.serde.LfPrintWriter;
-import cuchaz.enigma.translation.mapping.serde.MappingHelper;
-import cuchaz.enigma.translation.mapping.serde.MappingsWriter;
+import cuchaz.enigma.translation.mapping.serde.*;
 import cuchaz.enigma.translation.mapping.tree.EntryTree;
 import cuchaz.enigma.translation.mapping.tree.EntryTreeNode;
-import cuchaz.enigma.translation.representation.entry.ClassEntry;
-import cuchaz.enigma.translation.representation.entry.Entry;
-import cuchaz.enigma.translation.representation.entry.FieldEntry;
-import cuchaz.enigma.translation.representation.entry.LocalVariableEntry;
-import cuchaz.enigma.translation.representation.entry.MethodEntry;
+import cuchaz.enigma.translation.representation.entry.*;
 import cuchaz.enigma.utils.I18n;
 
 public enum EnigmaMappingsWriter implements MappingsWriter {
@@ -184,19 +173,22 @@ public enum EnigmaMappingsWriter implements MappingsWriter {
 
                 EntryMapping classEntryMapping = mappings.get(classEntry);
 
+                if (classEntryMapping == null) {
+                        classEntryMapping = EntryMapping.DEFAULT;
+                }
+
                 writer.println(writeClass(classEntry, classEntryMapping).trim());
-                if (classEntryMapping != null && classEntryMapping.getJavadoc() != null) {
+                if (classEntryMapping.javadoc() != null) {
                         writeDocs(writer, classEntryMapping, 0);
                 }
 
                 for (Entry<?> child : children) {
                         writeEntry(writer, mappings, child, 1);
                 }
-
         }
 
         private void writeDocs(PrintWriter writer, EntryMapping mapping, int depth) {
-                String jd = mapping.getJavadoc();
+                String jd = mapping.javadoc();
                 if (jd != null) {
                         for (String line : jd.split("\\R")) {
                                 writer.println(indent(EnigmaFormat.COMMENT + " " + MappingHelper.escape(line), depth + 1));
@@ -212,20 +204,26 @@ public enum EnigmaMappingsWriter implements MappingsWriter {
 
                 EntryMapping mapping = node.getValue();
 
-                if (entry instanceof ClassEntry) {
-                        String line = writeClass((ClassEntry) entry, mapping);
-                        writer.println(indent(line, depth));
-                } else if (entry instanceof MethodEntry) {
-                        String line = writeMethod((MethodEntry) entry, mapping);
-                        writer.println(indent(line, depth));
-                } else if (entry instanceof FieldEntry) {
-                        String line = writeField((FieldEntry) entry, mapping);
-                        writer.println(indent(line, depth));
-                } else if (entry instanceof LocalVariableEntry && mapping != null) {
-                        String line = writeArgument((LocalVariableEntry) entry, mapping);
+                if (mapping == null) {
+                        mapping = EntryMapping.DEFAULT;
+                }
+
+                String line = null;
+                if (entry instanceof ClassEntry classEntry) {
+                        line = writeClass(classEntry, mapping);
+                } else if (entry instanceof MethodEntry methodEntry) {
+                        line = writeMethod(methodEntry, mapping);
+                } else if (entry instanceof FieldEntry fieldEntry) {
+                        line = writeField(fieldEntry, mapping);
+                } else if (entry instanceof LocalVariableEntry varEntry && mapping.targetName() != null) {
+                        line = writeArgument(varEntry, mapping);
+                }
+
+                if (line != null) {
                         writer.println(indent(line, depth));
                 }
-                if (mapping != null && mapping.getJavadoc() != null) {
+
+                if (mapping.javadoc() != null) {
                         writeDocs(writer, mapping, depth);
                 }
 
@@ -254,55 +252,53 @@ public enum EnigmaMappingsWriter implements MappingsWriter {
                                 .forEach(result::add);
 
                 children.stream().filter(e -> e instanceof ClassEntry)
-                                                .map(e -> (ClassEntry) e)
-                                                .sorted()
-                                                .forEach(result::add);
+                                .map(e -> (ClassEntry) e)
+                                .sorted()
+                                .forEach(result::add);
 
                 return result;
         }
 
-        protected String writeClass(ClassEntry entry, EntryMapping mapping) {
-                StringBuilder builder = new StringBuilder(EnigmaFormat.CLASS +" ");
+        protected String writeClass(ClassEntry entry, @Nonnull EntryMapping mapping) {
+                StringBuilder builder = new StringBuilder(EnigmaFormat.CLASS + " ");
                 builder.append(entry.getName()).append(' ');
                 writeMapping(builder, mapping);
 
                 return builder.toString();
         }
 
-        protected String writeMethod(MethodEntry entry, EntryMapping mapping) {
+        protected String writeMethod(MethodEntry entry, @Nonnull EntryMapping mapping) {
                 StringBuilder builder = new StringBuilder(EnigmaFormat.METHOD + " ");
                 builder.append(entry.getName()).append(' ');
-                if (mapping != null && !mapping.getTargetName().equals(entry.getName())) {
-                        writeMapping(builder, mapping);
-                }
+                writeMapping(builder, mapping);
 
                 builder.append(entry.getDesc().toString());
 
                 return builder.toString();
         }
 
-        protected String writeField(FieldEntry entry, EntryMapping mapping) {
+        protected String writeField(FieldEntry entry, @Nonnull EntryMapping mapping) {
                 StringBuilder builder = new StringBuilder(EnigmaFormat.FIELD + " ");
                 builder.append(entry.getName()).append(' ');
-                if (mapping != null && !mapping.getTargetName().equals(entry.getName())) {
-                        writeMapping(builder, mapping);
-                }
+                writeMapping(builder, mapping);
 
                 builder.append(entry.getDesc().toString());
 
                 return builder.toString();
         }
 
-        protected String writeArgument(LocalVariableEntry entry, EntryMapping mapping) {
-                return EnigmaFormat.PARAMETER + " " + entry.getIndex() + ' ' + mapping.getTargetName();
+        protected String writeArgument(LocalVariableEntry entry, @Nonnull EntryMapping mapping) {
+                return EnigmaFormat.PARAMETER + " " + entry.getIndex() + ' ' + mapping.targetName();
         }
 
         private void writeMapping(StringBuilder builder, EntryMapping mapping) {
-                if (mapping != null) {
-                        builder.append(mapping.getTargetName()).append(' ');
-                        if (mapping.getAccessModifier() != AccessModifier.UNCHANGED) {
-                                builder.append(mapping.getAccessModifier().getFormattedName()).append(' ');
+                if (mapping.targetName() != null) {
+                        builder.append(mapping.targetName()).append(' ');
+                        if (mapping.accessModifier() != AccessModifier.UNCHANGED) {
+                                builder.append(mapping.accessModifier().getFormattedName()).append(' ');
                         }
+                } else if (mapping.accessModifier() != AccessModifier.UNCHANGED) {
+                        builder.append("- ").append(mapping.accessModifier().getFormattedName()).append(' ');
                 }
         }
 
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/tiny/TinyMappingsWriter.java b/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/tiny/TinyMappingsWriter.java
index 4f78e6f3..1f785e10 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/tiny/TinyMappingsWriter.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/tiny/TinyMappingsWriter.java
@@ -73,13 +73,16 @@ public class TinyMappingsWriter implements MappingsWriter {
         Translator translator = new MappingTranslator(mappings, VoidEntryResolver.INSTANCE);
 
         EntryMapping mapping = mappings.get(entry);
-        if (mapping != null && !entry.getName().equals(mapping.getTargetName())) {
+
+        // Do not write mappings without deobfuscated name since tiny v1 doesn't
+        // support comments anyway
+                if (mapping != null && mapping.targetName() != null) {
             if (entry instanceof ClassEntry) {
                 writeClass(writer, (ClassEntry) entry, translator);
             } else if (entry instanceof FieldEntry) {
-                writeLine(writer, serializeEntry(entry, mapping.getTargetName()));
+                                writeLine(writer, serializeEntry(entry, mapping.targetName()));
             } else if (entry instanceof MethodEntry) {
-                writeLine(writer, serializeEntry(entry, mapping.getTargetName()));
+                                writeLine(writer, serializeEntry(entry, mapping.targetName()));
             }
         }
 
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/tinyv2/TinyV2Writer.java b/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/tinyv2/TinyV2Writer.java
index 5160eda3..c4005688 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/tinyv2/TinyV2Writer.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/mapping/serde/tinyv2/TinyV2Writer.java
@@ -62,8 +62,8 @@ public final class TinyV2Writer implements MappingsWriter {
                 Deque<String> parts = new LinkedList<>();
                 do {
                         EntryMapping mapping = tree.get(classEntry);
-                        if (mapping != null) {
-                                parts.addFirst(mapping.getTargetName());
+                        if (mapping != null && mapping.targetName() != null) {
+                                parts.addFirst(mapping.targetName());
                         } else {
                                 parts.addFirst(classEntry.getName());
                         }
@@ -81,7 +81,7 @@ public final class TinyV2Writer implements MappingsWriter {
                 writeComment(writer, node.getValue(), 1);
 
                 for (EntryTreeNode<EntryMapping> child : node.getChildNodes()) {
-                        Entry entry = child.getEntry();
+                        Entry<?> entry = child.getEntry();
                         if (entry instanceof FieldEntry) {
                                 writeField(writer, child);
                         } else if (entry instanceof MethodEntry) {
@@ -98,16 +98,21 @@ public final class TinyV2Writer implements MappingsWriter {
                 writer.print(node.getEntry().getName());
                 writer.print("\t");
                 EntryMapping mapping = node.getValue();
+
                 if (mapping == null) {
-                        writer.println(node.getEntry().getName()); // todo fix v2 name inference
-                } else {
-                        writer.println(mapping.getTargetName());
+                        mapping = EntryMapping.DEFAULT;
+                }
 
-                        writeComment(writer, mapping, 2);
+                if (mapping.targetName() != null) {
+                        writer.println(mapping.targetName());
+                } else {
+                        writer.println(node.getEntry().getName()); // todo fix v2 name inference
                 }
 
+                writeComment(writer, mapping, 2);
+
                 for (EntryTreeNode<EntryMapping> child : node.getChildNodes()) {
-                        Entry entry = child.getEntry();
+                        Entry<?> entry = child.getEntry();
                         if (entry instanceof LocalVariableEntry) {
                                 writeParameter(writer, child);
                         }
@@ -116,7 +121,7 @@ public final class TinyV2Writer implements MappingsWriter {
         }
 
         private void writeField(PrintWriter writer, EntryTreeNode<EntryMapping> node) {
-                if (node.getValue() == null)
+                if (node.getValue() == null || node.getValue().equals(EntryMapping.DEFAULT))
                         return; // Shortcut
 
                 writer.print(indent(1));
@@ -126,17 +131,22 @@ public final class TinyV2Writer implements MappingsWriter {
                 writer.print(node.getEntry().getName());
                 writer.print("\t");
                 EntryMapping mapping = node.getValue();
+
                 if (mapping == null) {
-                        writer.println(node.getEntry().getName()); // todo fix v2 name inference
-                } else {
-                        writer.println(mapping.getTargetName());
+                        mapping = EntryMapping.DEFAULT;
+                }
 
-                        writeComment(writer, mapping, 2);
+                if (mapping.targetName() != null) {
+                        writer.println(mapping.targetName());
+                } else {
+                        writer.println(node.getEntry().getName()); // todo fix v2 name inference
                 }
+
+                writeComment(writer, mapping, 2);
         }
 
         private void writeParameter(PrintWriter writer, EntryTreeNode<EntryMapping> node) {
-                if (node.getValue() == null)
+                if (node.getValue() == null || node.getValue().equals(EntryMapping.DEFAULT))
                         return; // Shortcut
 
                 writer.print(indent(2));
@@ -146,20 +156,20 @@ public final class TinyV2Writer implements MappingsWriter {
                 writer.print(node.getEntry().getName());
                 writer.print("\t");
                 EntryMapping mapping = node.getValue();
-                if (mapping == null) {
+                if (mapping == null || mapping.targetName() == null) {
                         writer.println(); // todo ???
                 } else {
-                        writer.println(mapping.getTargetName());
+                        writer.println(mapping.targetName());
 
                         writeComment(writer, mapping, 3);
                 }
         }
 
         private void writeComment(PrintWriter writer, EntryMapping mapping, int indent) {
-                if (mapping != null && mapping.getJavadoc() != null) {
+                if (mapping != null && mapping.javadoc() != null) {
                         writer.print(indent(indent));
                         writer.print("c\t");
-                        writer.print(MappingHelper.escape(mapping.getJavadoc()));
+                        writer.print(MappingHelper.escape(mapping.javadoc()));
                         writer.println();
                 }
         }
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/mapping/tree/HashEntryTree.java b/enigma/src/main/java/cuchaz/enigma/translation/mapping/tree/HashEntryTree.java
index 570941cd..0992d342 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/mapping/tree/HashEntryTree.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/mapping/tree/HashEntryTree.java
@@ -6,6 +6,7 @@ import cuchaz.enigma.translation.mapping.EntryMapping;
 import cuchaz.enigma.translation.mapping.EntryResolver;
 import cuchaz.enigma.translation.representation.entry.Entry;
 
+import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 import java.util.*;
 import java.util.function.Function;
@@ -152,6 +153,7 @@ public class HashEntryTree<T> implements EntryTree<T> {
         }
 
         @Override
+        @Nonnull
         public Iterator<EntryTreeNode<T>> iterator() {
                 Collection<EntryTreeNode<T>> nodes = new ArrayList<>();
                 for (EntryTreeNode<T> node : root.values()) {
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/representation/Lambda.java b/enigma/src/main/java/cuchaz/enigma/translation/representation/Lambda.java
index a6aed731..13c7cd48 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/representation/Lambda.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/representation/Lambda.java
@@ -35,9 +35,9 @@ public class Lambda implements Translatable {
                 EntryMapping samMethodMapping = resolveMapping(resolver, mappings, samMethod);
 
                 return TranslateResult.of(
-                                samMethodMapping == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
+                                samMethodMapping.targetName() == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
                                 new Lambda(
-                                                samMethodMapping != null ? samMethodMapping.getTargetName() : invokedName,
+                                                samMethodMapping.targetName() != null ? samMethodMapping.targetName() : invokedName,
                                                 invokedType.extendedTranslate(translator, resolver, mappings).getValue(),
                                                 samMethodType.extendedTranslate(translator, resolver, mappings).getValue(),
                                                 implMethod.extendedTranslate(translator, resolver, mappings).getValue(),
@@ -53,7 +53,7 @@ public class Lambda implements Translatable {
                                 return mapping;
                         }
                 }
-                return null;
+                return EntryMapping.DEFAULT;
         }
 
         public ClassEntry getInterface() {
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/ClassDefEntry.java b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/ClassDefEntry.java
index b0fd2865..237c93dc 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/ClassDefEntry.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/ClassDefEntry.java
@@ -13,6 +13,7 @@ package cuchaz.enigma.translation.representation.entry;
 
 import java.util.Arrays;
 
+import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
 import com.google.common.base.Preconditions;
@@ -75,15 +76,15 @@ public class ClassDefEntry extends ClassEntry implements DefEntry<ClassEntry> {
         }
 
         @Override
-        public TranslateResult<ClassDefEntry> extendedTranslate(Translator translator, @Nullable EntryMapping mapping) {
+        public TranslateResult<ClassDefEntry> extendedTranslate(Translator translator, @Nonnull EntryMapping mapping) {
                 Signature translatedSignature = translator.translate(signature);
-                String translatedName = mapping != null ? mapping.getTargetName() : name;
-                AccessFlags translatedAccess = mapping != null ? mapping.getAccessModifier().transform(access) : access;
+                String translatedName = mapping.targetName() != null ? mapping.targetName() : name;
+                AccessFlags translatedAccess = mapping.accessModifier().transform(access);
                 ClassEntry translatedSuper = translator.translate(superClass);
                 ClassEntry[] translatedInterfaces = Arrays.stream(interfaces).map(translator::translate).toArray(ClassEntry[]::new);
-                String docs = mapping != null ? mapping.getJavadoc() : null;
+                String docs = mapping.javadoc();
                 return TranslateResult.of(
-                                mapping == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
+                                mapping.targetName() == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
                                 new ClassDefEntry(parent, translatedName, translatedSignature, translatedAccess, translatedSuper, translatedInterfaces, docs)
                 );
         }
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/ClassEntry.java b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/ClassEntry.java
index fe56611b..ec5294ed 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/ClassEntry.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/ClassEntry.java
@@ -82,16 +82,16 @@ public class ClassEntry extends ParentedEntry<ClassEntry> implements Comparable<
         }
 
         @Override
-        public TranslateResult<? extends ClassEntry> extendedTranslate(Translator translator, @Nullable EntryMapping mapping) {
+        public TranslateResult<? extends ClassEntry> extendedTranslate(Translator translator, @Nonnull EntryMapping mapping) {
                 if (name.charAt(0) == '[') {
                         TranslateResult<TypeDescriptor> translatedName = translator.extendedTranslate(new TypeDescriptor(name));
                         return translatedName.map(desc -> new ClassEntry(parent, desc.toString()));
                 }
 
-                String translatedName = mapping != null ? mapping.getTargetName() : name;
-                String docs = mapping != null ? mapping.getJavadoc() : null;
+                String translatedName = mapping.targetName() != null ? mapping.targetName() : name;
+                String docs = mapping.javadoc();
                 return TranslateResult.of(
-                                mapping == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
+                                mapping.targetName() == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
                                 new ClassEntry(parent, translatedName, docs)
                 );
         }
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/Entry.java b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/Entry.java
index 8a81c54a..956f32ca 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/Entry.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/Entry.java
@@ -13,6 +13,7 @@ package cuchaz.enigma.translation.representation.entry;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 
 import javax.annotation.Nullable;
 
@@ -107,16 +108,29 @@ public interface Entry<P extends Entry<?>> extends Translatable {
 
         boolean canConflictWith(Entry<?> entry);
 
-        @Nullable
         default ClassEntry getContainingClass() {
-                P parent = getParent();
-                if (parent == null) {
-                        return null;
+                ClassEntry last = null;
+                Entry<?> current = this;
+                while (current != null) {
+                        if (current instanceof ClassEntry) {
+                                last = (ClassEntry) current;
+                                break;
+                        }
+                        current = current.getParent();
                 }
-                if (parent instanceof ClassEntry) {
-                        return (ClassEntry) parent;
+                return Objects.requireNonNull(last, () -> String.format("%s has no containing class?", this));
+        }
+
+        default ClassEntry getTopLevelClass() {
+                ClassEntry last = null;
+                Entry<?> current = this;
+                while (current != null) {
+                        if (current instanceof ClassEntry) {
+                                last = (ClassEntry) current;
+                        }
+                        current = current.getParent();
                 }
-                return parent.getContainingClass();
+                return Objects.requireNonNull(last, () -> String.format("%s has no top level class?", this));
         }
 
         default List<Entry<?>> getAncestry() {
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/FieldDefEntry.java b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/FieldDefEntry.java
index b9da6cca..0efb6a99 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/FieldDefEntry.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/FieldDefEntry.java
@@ -11,8 +11,6 @@
 
 package cuchaz.enigma.translation.representation.entry;
 
-import javax.annotation.Nullable;
-
 import com.google.common.base.Preconditions;
 
 import cuchaz.enigma.source.RenamableTokenType;
@@ -23,6 +21,8 @@ import cuchaz.enigma.translation.representation.AccessFlags;
 import cuchaz.enigma.translation.representation.Signature;
 import cuchaz.enigma.translation.representation.TypeDescriptor;
 
+import javax.annotation.Nonnull;
+
 public class FieldDefEntry extends FieldEntry implements DefEntry<ClassEntry> {
         private final AccessFlags access;
         private final Signature signature;
@@ -53,14 +53,14 @@ public class FieldDefEntry extends FieldEntry implements DefEntry<ClassEntry> {
         }
 
         @Override
-        protected TranslateResult<FieldEntry> extendedTranslate(Translator translator, @Nullable EntryMapping mapping) {
+        protected TranslateResult<FieldEntry> extendedTranslate(Translator translator, @Nonnull EntryMapping mapping) {
                 TypeDescriptor translatedDesc = translator.translate(desc);
                 Signature translatedSignature = translator.translate(signature);
-                String translatedName = mapping != null ? mapping.getTargetName() : name;
-                AccessFlags translatedAccess = mapping != null ? mapping.getAccessModifier().transform(access) : access;
-                String docs = mapping != null ? mapping.getJavadoc() : null;
+                String translatedName = mapping.targetName() != null ? mapping.targetName() : name;
+                AccessFlags translatedAccess = mapping.accessModifier().transform(access);
+                String docs = mapping.javadoc();
                 return TranslateResult.of(
-                                mapping == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
+                                mapping.targetName() == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
                                 new FieldDefEntry(parent, translatedName, translatedDesc, translatedSignature, translatedAccess, docs)
                 );
         }
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/FieldEntry.java b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/FieldEntry.java
index 5ddd33de..db940118 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/FieldEntry.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/FieldEntry.java
@@ -13,7 +13,7 @@ package cuchaz.enigma.translation.representation.entry;
 
 import java.util.Objects;
 
-import javax.annotation.Nullable;
+import javax.annotation.Nonnull;
 
 import com.google.common.base.Preconditions;
 
@@ -63,11 +63,11 @@ public class FieldEntry extends ParentedEntry<ClassEntry> implements Comparable<
         }
 
         @Override
-        protected TranslateResult<FieldEntry> extendedTranslate(Translator translator, @Nullable EntryMapping mapping) {
-                String translatedName = mapping != null ? mapping.getTargetName() : name;
-                String docs = mapping != null ? mapping.getJavadoc() : null;
+        protected TranslateResult<FieldEntry> extendedTranslate(Translator translator, @Nonnull EntryMapping mapping) {
+                String translatedName = mapping.targetName() != null ? mapping.targetName() : name;
+                String docs = mapping.javadoc();
                 return TranslateResult.of(
-                                mapping == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
+                                mapping.targetName() == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
                                 new FieldEntry(parent, translatedName, translator.translate(desc), docs)
                 );
         }
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/LocalVariableDefEntry.java b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/LocalVariableDefEntry.java
index 2712c65a..c151de4e 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/LocalVariableDefEntry.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/LocalVariableDefEntry.java
@@ -1,6 +1,6 @@
 package cuchaz.enigma.translation.representation.entry;
 
-import javax.annotation.Nullable;
+import javax.annotation.Nonnull;
 
 import com.google.common.base.Preconditions;
 
@@ -30,12 +30,12 @@ public class LocalVariableDefEntry extends LocalVariableEntry {
         }
 
         @Override
-        protected TranslateResult<LocalVariableEntry> extendedTranslate(Translator translator, @Nullable EntryMapping mapping) {
+        protected TranslateResult<LocalVariableEntry> extendedTranslate(Translator translator, @Nonnull EntryMapping mapping) {
                 TypeDescriptor translatedDesc = translator.translate(desc);
-                String translatedName = mapping != null ? mapping.getTargetName() : name;
-                String javadoc = mapping != null ? mapping.getJavadoc() : javadocs;
+                String translatedName = mapping.targetName() != null ? mapping.targetName() : name;
+                String javadoc = mapping.javadoc();
                 return TranslateResult.of(
-                                mapping == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
+                                mapping.targetName() == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
                                 new LocalVariableDefEntry(parent, index, translatedName, parameter, translatedDesc, javadoc)
                 );
         }
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/LocalVariableEntry.java b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/LocalVariableEntry.java
index 154f11fd..1cf1a832 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/LocalVariableEntry.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/LocalVariableEntry.java
@@ -2,7 +2,7 @@ package cuchaz.enigma.translation.representation.entry;
 
 import java.util.Objects;
 
-import javax.annotation.Nullable;
+import javax.annotation.Nonnull;
 
 import com.google.common.base.Preconditions;
 
@@ -50,11 +50,11 @@ public class LocalVariableEntry extends ParentedEntry<MethodEntry> implements Co
         }
 
         @Override
-        protected TranslateResult<LocalVariableEntry> extendedTranslate(Translator translator, @Nullable EntryMapping mapping) {
-                String translatedName = mapping != null ? mapping.getTargetName() : name;
-                String javadoc = mapping != null ? mapping.getJavadoc() : null;
+        protected TranslateResult<LocalVariableEntry> extendedTranslate(Translator translator, @Nonnull EntryMapping mapping) {
+                String translatedName = mapping.targetName() != null ? mapping.targetName() : name;
+                String javadoc = mapping.javadoc();
                 return TranslateResult.of(
-                                mapping == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
+                                mapping.targetName() == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
                                 new LocalVariableEntry(parent, index, translatedName, parameter, javadoc)
                 );
         }
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/MethodDefEntry.java b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/MethodDefEntry.java
index cc326d6a..30ef706e 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/MethodDefEntry.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/MethodDefEntry.java
@@ -11,7 +11,7 @@
 
 package cuchaz.enigma.translation.representation.entry;
 
-import javax.annotation.Nullable;
+import javax.annotation.Nonnull;
 
 import com.google.common.base.Preconditions;
 
@@ -53,14 +53,14 @@ public class MethodDefEntry extends MethodEntry implements DefEntry<ClassEntry>
         }
 
         @Override
-        protected TranslateResult<MethodDefEntry> extendedTranslate(Translator translator, @Nullable EntryMapping mapping) {
+        protected TranslateResult<MethodDefEntry> extendedTranslate(Translator translator, @Nonnull EntryMapping mapping) {
                 MethodDescriptor translatedDesc = translator.translate(descriptor);
                 Signature translatedSignature = translator.translate(signature);
-                String translatedName = mapping != null ? mapping.getTargetName() : name;
-                AccessFlags translatedAccess = mapping != null ? mapping.getAccessModifier().transform(access) : access;
-                String docs = mapping != null ? mapping.getJavadoc() : null;
+                String translatedName = mapping.targetName() != null ? mapping.targetName() : name;
+                AccessFlags translatedAccess = mapping.accessModifier().transform(access);
+                String docs = mapping.javadoc();
                 return TranslateResult.of(
-                                mapping == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
+                                mapping.targetName() == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
                                 new MethodDefEntry(parent, translatedName, translatedDesc, translatedSignature, translatedAccess, docs)
                 );
         }
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/MethodEntry.java b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/MethodEntry.java
index 864a5802..ab9c2d17 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/MethodEntry.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/MethodEntry.java
@@ -13,7 +13,7 @@ package cuchaz.enigma.translation.representation.entry;
 
 import java.util.Objects;
 
-import javax.annotation.Nullable;
+import javax.annotation.Nonnull;
 
 import com.google.common.base.Preconditions;
 
@@ -58,11 +58,11 @@ public class MethodEntry extends ParentedEntry<ClassEntry> implements Comparable
         }
 
         @Override
-        protected TranslateResult<? extends MethodEntry> extendedTranslate(Translator translator, @Nullable EntryMapping mapping) {
-                String translatedName = mapping != null ? mapping.getTargetName() : name;
-                String docs = mapping != null ? mapping.getJavadoc() : null;
+        protected TranslateResult<? extends MethodEntry> extendedTranslate(Translator translator, @Nonnull EntryMapping mapping) {
+                String translatedName = mapping.targetName() != null ? mapping.targetName() : name;
+                String docs = mapping.javadoc();
                 return TranslateResult.of(
-                                mapping == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
+                                mapping.targetName() == null ? RenamableTokenType.OBFUSCATED : RenamableTokenType.DEOBFUSCATED,
                                 new MethodEntry(parent, translatedName, translator.translate(descriptor), docs)
                 );
         }
diff --git a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/ParentedEntry.java b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/ParentedEntry.java
index 56348915..267bc11a 100644
--- a/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/ParentedEntry.java
+++ b/enigma/src/main/java/cuchaz/enigma/translation/representation/entry/ParentedEntry.java
@@ -11,6 +11,7 @@
 
 package cuchaz.enigma.translation.representation.entry;
 
+import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
 import com.google.common.base.Preconditions;
@@ -41,7 +42,7 @@ public abstract class ParentedEntry<P extends Entry<?>> implements Entry<P> {
         @Override
         public abstract ParentedEntry<P> withName(String name);
 
-        protected abstract TranslateResult<? extends ParentedEntry<P>> extendedTranslate(Translator translator, @Nullable EntryMapping mapping);
+        protected abstract TranslateResult<? extends ParentedEntry<P>> extendedTranslate(Translator translator, @Nonnull EntryMapping mapping);
 
         @Override
         public String getName() {
@@ -93,6 +94,6 @@ public abstract class ParentedEntry<P extends Entry<?>> implements Entry<P> {
                                 return mapping;
                         }
                 }
-                return null;
+                return EntryMapping.DEFAULT;
         }
 }
diff --git a/enigma/src/main/java/cuchaz/enigma/utils/TristateChange.java b/enigma/src/main/java/cuchaz/enigma/utils/TristateChange.java
new file mode 100644
index 00000000..864154cc
--- /dev/null
+++ b/enigma/src/main/java/cuchaz/enigma/utils/TristateChange.java
@@ -0,0 +1,78 @@
+package cuchaz.enigma.utils;
+
+import java.util.Objects;
+
+public final class TristateChange<T> {
+
+        private static final TristateChange<?> UNCHANGED = new TristateChange<>(Type.UNCHANGED, null);
+        private static final TristateChange<?> RESET = new TristateChange<>(Type.RESET, null);
+
+        private final Type type;
+        private final T val;
+
+        @SuppressWarnings("unchecked")
+        public static <T> TristateChange<T> unchanged() {
+                return (TristateChange<T>) TristateChange.UNCHANGED;
+        }
+
+        @SuppressWarnings("unchecked")
+        public static <T> TristateChange<T> reset() {
+                return (TristateChange<T>) TristateChange.RESET;
+        }
+
+        public static <T> TristateChange<T> set(T value) {
+                return new TristateChange<>(Type.SET, value);
+        }
+
+        private TristateChange(Type type, T val) {
+                this.type = type;
+                this.val = val;
+        }
+
+        public Type getType() {
+                return this.type;
+        }
+
+        public boolean isUnchanged() {
+                return this.type == Type.UNCHANGED;
+        }
+
+        public boolean isReset() {
+                return this.type == Type.RESET;
+        }
+
+        public boolean isSet() {
+                return this.type == Type.SET;
+        }
+
+        public T getNewValue() {
+                if (this.type != Type.SET) throw new IllegalStateException(String.format("No concrete value in %s", this));
+                return this.val;
+        }
+
+        @Override
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                TristateChange<?> that = (TristateChange<?>) o;
+                return type == that.type &&
+                                Objects.equals(val, that.val);
+        }
+
+        @Override
+        public int hashCode() {
+                return Objects.hash(type, val);
+        }
+
+        @Override
+        public String toString() {
+                return String.format("TristateChange { type: %s, val: %s }", type, val);
+        }
+
+        public enum Type {
+                UNCHANGED,
+                RESET,
+                SET,
+        }
+
+}
diff --git a/enigma/src/main/java/cuchaz/enigma/utils/validation/PrintValidatable.java b/enigma/src/main/java/cuchaz/enigma/utils/validation/PrintValidatable.java
index 81b6c43f..5067d7e3 100644
--- a/enigma/src/main/java/cuchaz/enigma/utils/validation/PrintValidatable.java
+++ b/enigma/src/main/java/cuchaz/enigma/utils/validation/PrintValidatable.java
@@ -1,5 +1,6 @@
 package cuchaz.enigma.utils.validation;
 
+import java.io.PrintStream;
 import java.util.Arrays;
 
 public class PrintValidatable implements Validatable {
@@ -8,6 +9,10 @@ public class PrintValidatable implements Validatable {
 
         @Override
         public void addMessage(ParameterizedMessage message) {
+                formatMessage(System.out, message);
+        }
+
+        public static void formatMessage(PrintStream w, ParameterizedMessage message) {
                 String text = message.getText();
                 String longText = message.getLongText();
                 String type = switch (message.message.type) {
@@ -15,9 +20,10 @@ public class PrintValidatable implements Validatable {
                         case WARNING -> "warning";
                         case ERROR -> "error";
                 };
-                System.out.printf("%s: %s\n", type, text);
+                w.printf("%s: %s\n", type, text);
+
                 if (!longText.isEmpty()) {
-                        Arrays.stream(longText.split("\n")).forEach(s -> System.out.printf("  %s\n", s));
+                        Arrays.stream(longText.split("\n")).forEach(s -> w.printf("  %s\n", s));
                 }
         }
 
diff --git a/enigma/src/main/java/cuchaz/enigma/utils/validation/ValidationContext.java b/enigma/src/main/java/cuchaz/enigma/utils/validation/ValidationContext.java
index ee2b5956..0ecb9fb3 100644
--- a/enigma/src/main/java/cuchaz/enigma/utils/validation/ValidationContext.java
+++ b/enigma/src/main/java/cuchaz/enigma/utils/validation/ValidationContext.java
@@ -62,6 +62,20 @@ public class ValidationContext {
                 return messages.stream().noneMatch(m -> m.message.type == Type.ERROR);
         }
 
+        /**
+         * If this validation context has at least one error, throw an exception.
+         *
+         * @throws IllegalStateException if errors are present
+         */
+        public void throwOnError() {
+                if (!this.canProceed()) {
+                        for (ParameterizedMessage message : this.messages) {
+                                PrintValidatable.formatMessage(System.err, message);
+                        }
+                        throw new IllegalStateException("Errors encountered; cannot continue! Check error log for details.");
+                }
+        }
+
         public List<ParameterizedMessage> getMessages() {
                 return Collections.unmodifiableList(messages);
         }
diff --git a/enigma/src/test/java/cuchaz/enigma/translation/mapping/TestReadWriteCycle.java b/enigma/src/test/java/cuchaz/enigma/translation/mapping/TestReadWriteCycle.java
index 4f6654a4..510dd3cd 100644
--- a/enigma/src/test/java/cuchaz/enigma/translation/mapping/TestReadWriteCycle.java
+++ b/enigma/src/test/java/cuchaz/enigma/translation/mapping/TestReadWriteCycle.java
@@ -85,18 +85,18 @@ public class TestReadWriteCycle {
                 Assert.assertTrue("Loaded mappings don't contain testMethod1", loadedMappings.contains(testMethod1.a));
                 Assert.assertTrue("Loaded mappings don't contain testMethod2", loadedMappings.contains(testMethod2.a));
 
-                Assert.assertEquals("Incorrect mapping: testClazz", testClazz.b.getTargetName(), loadedMappings.get(testClazz.a).getTargetName());
-                Assert.assertEquals("Incorrect mapping: testField1", testField1.b.getTargetName(), loadedMappings.get(testField1.a).getTargetName());
-                Assert.assertEquals("Incorrect mapping: testField2", testField2.b.getTargetName(), loadedMappings.get(testField2.a).getTargetName());
-                Assert.assertEquals("Incorrect mapping: testMethod1", testMethod1.b.getTargetName(), loadedMappings.get(testMethod1.a).getTargetName());
-                Assert.assertEquals("Incorrect mapping: testMethod2", testMethod2.b.getTargetName(), loadedMappings.get(testMethod2.a).getTargetName());
+                Assert.assertEquals("Incorrect mapping: testClazz", testClazz.b.targetName(), loadedMappings.get(testClazz.a).targetName());
+                Assert.assertEquals("Incorrect mapping: testField1", testField1.b.targetName(), loadedMappings.get(testField1.a).targetName());
+                Assert.assertEquals("Incorrect mapping: testField2", testField2.b.targetName(), loadedMappings.get(testField2.a).targetName());
+                Assert.assertEquals("Incorrect mapping: testMethod1", testMethod1.b.targetName(), loadedMappings.get(testMethod1.a).targetName());
+                Assert.assertEquals("Incorrect mapping: testMethod2", testMethod2.b.targetName(), loadedMappings.get(testMethod2.a).targetName());
 
                 if (supportsJavadoc) {
-                        Assert.assertEquals("Incorrect javadoc: testClazz", testClazz.b.getJavadoc(), loadedMappings.get(testClazz.a).getJavadoc());
-                        Assert.assertEquals("Incorrect javadoc: testField1", testField1.b.getJavadoc(), loadedMappings.get(testField1.a).getJavadoc());
-                        Assert.assertEquals("Incorrect javadoc: testField2", testField2.b.getJavadoc(), loadedMappings.get(testField2.a).getJavadoc());
-                        Assert.assertEquals("Incorrect javadoc: testMethod1", testMethod1.b.getJavadoc(), loadedMappings.get(testMethod1.a).getJavadoc());
-                        Assert.assertEquals("Incorrect javadoc: testMethod2", testMethod2.b.getJavadoc(), loadedMappings.get(testMethod2.a).getJavadoc());
+                        Assert.assertEquals("Incorrect javadoc: testClazz", testClazz.b.javadoc(), loadedMappings.get(testClazz.a).javadoc());
+                        Assert.assertEquals("Incorrect javadoc: testField1", testField1.b.javadoc(), loadedMappings.get(testField1.a).javadoc());
+                        Assert.assertEquals("Incorrect javadoc: testField2", testField2.b.javadoc(), loadedMappings.get(testField2.a).javadoc());
+                        Assert.assertEquals("Incorrect javadoc: testMethod1", testMethod1.b.javadoc(), loadedMappings.get(testMethod1.a).javadoc());
+                        Assert.assertEquals("Incorrect javadoc: testMethod2", testMethod2.b.javadoc(), loadedMappings.get(testMethod2.a).javadoc());
                 }
 
                 tempFile.delete();