Fixed uuid code that was prematurely pushed.

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

@@ -980,6 +980,7 @@ public abstract class Entity {
         // CraftBukkit end
 
         // CraftBukkit start - reset world
+        if (this instanceof EntityPlayer) {
             org.bukkit.Server server = Bukkit.getServer();
             org.bukkit.World bworld = null;
 
@@ -992,12 +993,13 @@ public abstract class Entity {
             } else {
                 bworld = server.getWorld(worldName);
             }
-        if(bworld == null && this instanceof EntityPlayer) {
+            if (bworld == null) {
                 EntityPlayer entityPlayer = (EntityPlayer) this;
                 bworld = ((org.bukkit.craftbukkit.CraftServer) server).getServer().getWorldServer(entityPlayer.dimension).getWorld();
             }
 
             this.spawnIn(bworld == null ? null : ((org.bukkit.craftbukkit.CraftWorld) bworld).getHandle());
+        }
         // CraftBukkit end
     }
 

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

@@ -2,7 +2,7 @@ package net.minecraft.server;
 
 import java.io.File;
 import java.util.List;
-import java.util.UUID;
+import java.util.UUID; // CraftBukkit
 
 public interface IDataManager {
 
@@ -22,5 +22,5 @@ public interface IDataManager {
 
     File b(String s);
 
-    UUID getUUID();
+    UUID getUUID(); // CraftBukkit
 }

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

@@ -9,9 +9,10 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.util.List;
-import java.util.UUID;
 import java.util.logging.Logger;
 
+import java.util.UUID; // CraftBukkit
+
 public class PlayerNBTManager implements PlayerFileData, IDataManager {
 
     private static final Logger a = Logger.getLogger("Minecraft");
@@ -19,6 +20,7 @@ public class PlayerNBTManager implements PlayerFileData, IDataManager {
     private final File c;
     private final File d;
     private final long e = System.currentTimeMillis();
+    private UUID uuid = null; // CraftBukkit
 
     public PlayerNBTManager(File file1, String s, boolean flag) {
         this.b = new File(file1, s);
@@ -223,20 +225,22 @@ public class PlayerNBTManager implements PlayerFileData, IDataManager {
 
     // CraftBukkit start
     public UUID getUUID() {
+        if (uuid != null) return uuid;
         try {
             File file1 = new File(this.b, "uid.dat");
-            UUID id;
             if (!file1.exists()) {
                 DataOutputStream dos = new DataOutputStream(new FileOutputStream(file1));
-                id = UUID.randomUUID();
+                uuid = UUID.randomUUID();
-                dos.writeLong(id.getMostSignificantBits());
+                dos.writeLong(uuid.getMostSignificantBits());
-                dos.writeLong(id.getLeastSignificantBits());
+                dos.writeLong(uuid.getLeastSignificantBits());
+                dos.close();
             }
             else {
                 DataInputStream dis = new DataInputStream(new FileInputStream(file1));
-                id = new UUID(dis.readLong(), dis.readLong());
+                uuid = new UUID(dis.readLong(), dis.readLong());
+                dis.close();
             }
-            return id;
+            return uuid;
         }
         catch (IOException ex) {
             return null;

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

@@ -8,9 +8,10 @@ import java.util.List;
 import java.util.Random;
 import java.util.Set;
 import java.util.TreeSet;
-import java.util.UUID;
 
 // CraftBukkit start
+import java.util.UUID;
+
 import org.bukkit.Bukkit;
 import org.bukkit.Location;
 import org.bukkit.generator.ChunkGenerator;
@@ -2415,4 +2416,5 @@ public class World implements IBlockAccess {
     public UUID getUUID() {
         return this.w.getUUID();
     }
+    // CraftBukkit end
 }

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

@@ -4,9 +4,10 @@ import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.UUID;
 
 // CraftBukkit start
+import java.util.UUID;
+
 import org.bukkit.Bukkit;
 import org.bukkit.craftbukkit.CraftServer;
 import org.bukkit.craftbukkit.CraftWorld;