From e67b7218fe1029438873286490ca2514d8a9df16 Mon Sep 17 00:00:00 2001
From: md_5 <md_5@live.com.au>
Date: Thu, 21 Mar 2013 17:00:54 +1100
Subject: [PATCH] Stage DataWatcher & WatchableObject.

So that we may identify the exact cause of exceptions originating from these classes.

diff --git a/src/main/java/net/minecraft/server/DataWatcher.java b/src/main/java/net/minecraft/server/DataWatcher.java
new file mode 100644
index 0000000..f0fa9ca
--- /dev/null
+++ b/src/main/java/net/minecraft/server/DataWatcher.java
@@ -0,0 +1,287 @@
+package net.minecraft.server;
+
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.locks.ReadWriteLock;
+import java.util.concurrent.locks.ReentrantReadWriteLock;
+
+public class DataWatcher {
+
+    private boolean a = true;
+    private static final HashMap b = new HashMap();
+    private final Map c = new HashMap();
+    private boolean d;
+    private ReadWriteLock e = new ReentrantReadWriteLock();
+
+    public DataWatcher() {}
+
+    public void a(int i, Object object) {
+        Integer integer = (Integer) b.get(object.getClass());
+
+        if (integer == null) {
+            throw new IllegalArgumentException("Unknown data type: " + object.getClass());
+        } else if (i > 31) {
+            throw new IllegalArgumentException("Data value id is too big with " + i + "! (Max is " + 31 + ")");
+        } else if (this.c.containsKey(Integer.valueOf(i))) {
+            throw new IllegalArgumentException("Duplicate id value for " + i + "!");
+        } else {
+            WatchableObject watchableobject = new WatchableObject(integer.intValue(), i, object);
+
+            this.e.writeLock().lock();
+            this.c.put(Integer.valueOf(i), watchableobject);
+            this.e.writeLock().unlock();
+            this.a = false;
+        }
+    }
+
+    public void a(int i, int j) {
+        WatchableObject watchableobject = new WatchableObject(j, i, null);
+
+        this.e.writeLock().lock();
+        this.c.put(Integer.valueOf(i), watchableobject);
+        this.e.writeLock().unlock();
+        this.a = false;
+    }
+
+    public byte getByte(int i) {
+        return ((Byte) this.i(i).b()).byteValue();
+    }
+
+    public short getShort(int i) {
+        return ((Short) this.i(i).b()).shortValue();
+    }
+
+    public int getInt(int i) {
+        return ((Integer) this.i(i).b()).intValue();
+    }
+
+    public String getString(int i) {
+        return (String) this.i(i).b();
+    }
+
+    public ItemStack getItemStack(int i) {
+        return (ItemStack) this.i(i).b();
+    }
+
+    private WatchableObject i(int i) {
+        this.e.readLock().lock();
+
+        WatchableObject watchableobject;
+
+        try {
+            watchableobject = (WatchableObject) this.c.get(Integer.valueOf(i));
+        } catch (Throwable throwable) {
+            CrashReport crashreport = CrashReport.a(throwable, "Getting synched entity data");
+            CrashReportSystemDetails crashreportsystemdetails = crashreport.a("Synched entity data");
+
+            crashreportsystemdetails.a("Data ID", Integer.valueOf(i));
+            throw new ReportedException(crashreport);
+        }
+
+        this.e.readLock().unlock();
+        return watchableobject;
+    }
+
+    public void watch(int i, Object object) {
+        WatchableObject watchableobject = this.i(i);
+
+        if (!object.equals(watchableobject.b())) {
+            watchableobject.a(object);
+            watchableobject.a(true);
+            this.d = true;
+        }
+    }
+
+    public void h(int i) {
+        WatchableObject.a(this.i(i), true);
+        this.d = true;
+    }
+
+    public boolean a() {
+        return this.d;
+    }
+
+    public static void a(List list, DataOutputStream dataoutputstream) throws IOException { // Spigot
+        if (list != null) {
+            Iterator iterator = list.iterator();
+
+            while (iterator.hasNext()) {
+                WatchableObject watchableobject = (WatchableObject) iterator.next();
+
+                a(dataoutputstream, watchableobject);
+            }
+        }
+
+        dataoutputstream.writeByte(127);
+    }
+
+    public List b() {
+        ArrayList arraylist = null;
+
+        if (this.d) {
+            this.e.readLock().lock();
+            Iterator iterator = this.c.values().iterator();
+
+            while (iterator.hasNext()) {
+                WatchableObject watchableobject = (WatchableObject) iterator.next();
+
+                if (watchableobject.d()) {
+                    watchableobject.a(false);
+                    if (arraylist == null) {
+                        arraylist = new ArrayList();
+                    }
+
+                    arraylist.add(watchableobject);
+                }
+            }
+
+            this.e.readLock().unlock();
+        }
+
+        this.d = false;
+        return arraylist;
+    }
+
+    public void a(DataOutputStream dataoutputstream) throws IOException { // Spigot
+        this.e.readLock().lock();
+        Iterator iterator = this.c.values().iterator();
+
+        while (iterator.hasNext()) {
+            WatchableObject watchableobject = (WatchableObject) iterator.next();
+
+            a(dataoutputstream, watchableobject);
+        }
+
+        this.e.readLock().unlock();
+        dataoutputstream.writeByte(127);
+    }
+
+    public List c() {
+        ArrayList arraylist = null;
+
+        this.e.readLock().lock();
+
+        WatchableObject watchableobject;
+
+        for (Iterator iterator = this.c.values().iterator(); iterator.hasNext(); arraylist.add(watchableobject)) {
+            watchableobject = (WatchableObject) iterator.next();
+            if (arraylist == null) {
+                arraylist = new ArrayList();
+            }
+        }
+
+        this.e.readLock().unlock();
+        return arraylist;
+    }
+
+    private static void a(DataOutputStream dataoutputstream, WatchableObject watchableobject) throws IOException { // Spigot
+        int i = (watchableobject.c() << 5 | watchableobject.a() & 31) & 255;
+
+        dataoutputstream.writeByte(i);
+        switch (watchableobject.c()) {
+        case 0:
+            dataoutputstream.writeByte(((Byte) watchableobject.b()).byteValue());
+            break;
+
+        case 1:
+            dataoutputstream.writeShort(((Short) watchableobject.b()).shortValue());
+            break;
+
+        case 2:
+            dataoutputstream.writeInt(((Integer) watchableobject.b()).intValue());
+            break;
+
+        case 3:
+            dataoutputstream.writeFloat(((Float) watchableobject.b()).floatValue());
+            break;
+
+        case 4:
+            Packet.a((String) watchableobject.b(), dataoutputstream);
+            break;
+
+        case 5:
+            ItemStack itemstack = (ItemStack) watchableobject.b();
+
+            Packet.a(itemstack, dataoutputstream);
+            break;
+
+        case 6:
+            ChunkCoordinates chunkcoordinates = (ChunkCoordinates) watchableobject.b();
+
+            dataoutputstream.writeInt(chunkcoordinates.x);
+            dataoutputstream.writeInt(chunkcoordinates.y);
+            dataoutputstream.writeInt(chunkcoordinates.z);
+        }
+    }
+
+    public static List a(DataInputStream datainputstream) throws IOException { // Spigot
+        ArrayList arraylist = null;
+
+        for (byte b0 = datainputstream.readByte(); b0 != 127; b0 = datainputstream.readByte()) {
+            if (arraylist == null) {
+                arraylist = new ArrayList();
+            }
+
+            int i = (b0 & 224) >> 5;
+            int j = b0 & 31;
+            WatchableObject watchableobject = null;
+
+            switch (i) {
+            case 0:
+                watchableobject = new WatchableObject(i, j, Byte.valueOf(datainputstream.readByte()));
+                break;
+
+            case 1:
+                watchableobject = new WatchableObject(i, j, Short.valueOf(datainputstream.readShort()));
+                break;
+
+            case 2:
+                watchableobject = new WatchableObject(i, j, Integer.valueOf(datainputstream.readInt()));
+                break;
+
+            case 3:
+                watchableobject = new WatchableObject(i, j, Float.valueOf(datainputstream.readFloat()));
+                break;
+
+            case 4:
+                watchableobject = new WatchableObject(i, j, Packet.a(datainputstream, 64));
+                break;
+
+            case 5:
+                watchableobject = new WatchableObject(i, j, Packet.c(datainputstream));
+                break;
+
+            case 6:
+                int k = datainputstream.readInt();
+                int l = datainputstream.readInt();
+                int i1 = datainputstream.readInt();
+
+                watchableobject = new WatchableObject(i, j, new ChunkCoordinates(k, l, i1));
+            }
+
+            arraylist.add(watchableobject);
+        }
+
+        return arraylist;
+    }
+
+    public boolean d() {
+        return this.a;
+    }
+
+    static {
+        b.put(Byte.class, Integer.valueOf(0));
+        b.put(Short.class, Integer.valueOf(1));
+        b.put(Integer.class, Integer.valueOf(2));
+        b.put(Float.class, Integer.valueOf(3));
+        b.put(String.class, Integer.valueOf(4));
+        b.put(ItemStack.class, Integer.valueOf(5));
+        b.put(ChunkCoordinates.class, Integer.valueOf(6));
+    }
+}
diff --git a/src/main/java/net/minecraft/server/WatchableObject.java b/src/main/java/net/minecraft/server/WatchableObject.java
new file mode 100644
index 0000000..678aa91
--- /dev/null
+++ b/src/main/java/net/minecraft/server/WatchableObject.java
@@ -0,0 +1,44 @@
+package net.minecraft.server;
+
+public class WatchableObject {
+
+    private final int a;
+    private final int b;
+    private Object c;
+    private boolean d;
+
+    public WatchableObject(int i, int j, Object object) {
+        this.b = j;
+        this.c = object;
+        this.a = i;
+        this.d = true;
+    }
+
+    public int a() {
+        return this.b;
+    }
+
+    public void a(Object object) {
+        this.c = object;
+    }
+
+    public Object b() {
+        return this.c;
+    }
+
+    public int c() {
+        return this.a;
+    }
+
+    public boolean d() {
+        return this.d;
+    }
+
+    public void a(boolean flag) {
+        this.d = flag;
+    }
+
+    static boolean a(WatchableObject watchableobject, boolean flag) {
+        return watchableobject.d = flag;
+    }
+}
-- 
1.8.1.2