Fix map chunk decompressing itself

src/main/java/net/minecraft/server/Packet.java

@@ -42,9 +42,9 @@ public abstract class Packet {
         }
     }
 
-    public abstract void a(DataInputStream datainputstream);
+    public abstract void a(DataInputStream datainputstream) throws IOException;
 
-    public abstract void a(DataOutputStream dataoutputstream);
+    public abstract void a(DataOutputStream dataoutputstream) throws IOException;
 
     public abstract void handle(NetHandler nethandler);
 

src/main/java/net/minecraft/server/Packet51MapChunk.java

@@ -0,0 +1,33 @@
+package net.minecraft.server;
+
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+public class Packet51MapChunk extends Packet {
+
+    @Override
+    public void a(DataInputStream datainputstream) throws IOException {
+        datainputstream.readInt();
+        datainputstream.readInt();
+        datainputstream.readBoolean();
+        datainputstream.readShort();
+        datainputstream.readShort();
+        int size = datainputstream.readInt();
+        byte[] buf = new byte[size];
+        datainputstream.readFully(buf, 0, size);
+    }
+
+    @Override
+    public void a(DataOutputStream dataoutputstream) throws IOException {
+    }
+
+    @Override
+    public void handle(NetHandler nethandler) {
+    }
+
+    @Override
+    public int a() {
+        return 0;
+    }
+}