diff --git a/lib/java/src/protocol/TBinaryProtocol.java b/lib/java/src/protocol/TBinaryProtocol.java
index 3aaa06b..b2e77d9 100644
--- a/lib/java/src/protocol/TBinaryProtocol.java
+++ b/lib/java/src/protocol/TBinaryProtocol.java
@@ -23,7 +23,7 @@
                                TField     field)   throws TException {
     return
       writeByte(out, field.type.getCode()) +
-      writeU32(out, field.id);
+      writeI32(out, field.id);
   }
 
   public int writeFieldEnd    (TTransport out)     throws TException {
@@ -40,7 +40,7 @@
     return
       writeByte(out, map.keyType.getCode()) +
       writeByte(out, map.valueType.getCode()) +
-      writeU32(out, map.size);
+      writeI32(out, map.size);
   }
 
   public int writeMapEnd      (TTransport out)     throws TException {
@@ -51,7 +51,7 @@
                                TList      list)    throws TException {
     return
       writeByte(out, list.elemType.getCode()) +
-      writeU32(out, list.size);
+      writeI32(out, list.size);
   }
 
   public int writeListEnd     (TTransport out)     throws TException {
@@ -62,7 +62,7 @@
                                TSet       set)     throws TException {
     return
       writeByte(out, set.elemType.getCode()) +
-      writeU32(out, set.size);
+      writeI32(out, set.size);
   }
 
   public int writeSetEnd      (TTransport out)     throws TException {
@@ -102,7 +102,7 @@
   public int writeString      (TTransport out,
                                TString    str)     throws TException {
     byte[] dat = str.value.getBytes();
-    int sent = writeU32(out, new UInt32(dat.length));
+    int sent = writeI32(out, new Int32(dat.length));
     out.write(dat, 0, dat.length);
     return sent + dat.length;
   }
@@ -129,10 +129,10 @@
     recv += readByte(in, t);
     field.type = TType.getType(t);
     if (field.type.equals(TType.STOP)) {
-      field.id = new UInt32(0);
+      field.id = new Int32(0);
       return recv;
     }
-    recv += readU32(in, field.id);
+    recv += readI32(in, field.id);
     return recv;
   }
   
@@ -148,7 +148,7 @@
     map.keyType = TType.getType(t);
     recv += readByte(in, t);
     map.valueType = TType.getType(t);
-    recv += readU32(in, map.size);
+    recv += readI32(in, map.size);
     return recv;
   }
 
@@ -162,7 +162,7 @@
     UInt8 t = new UInt8();
     recv += readByte(in, t);
     list.elemType = TType.getType(t);
-    recv += readU32(in, list.size);
+    recv += readI32(in, list.size);
     return recv;
   }
 
@@ -176,7 +176,7 @@
     UInt8 t = new UInt8();
     recv += readByte(in, t);
     set.elemType = TType.getType(t);
-    recv += readU32(in, set.size);
+    recv += readI32(in, set.size);
     return recv;
   }
 
@@ -226,11 +226,11 @@
 
   public int readString       (TTransport  in,
                                TString     s)      throws TException {
-    UInt32 size = new UInt32();
-    int recv = readU32(in, size);
-    byte[] buf = new byte[size.toInt()];
-    in.readAll(buf, 0, size.toInt());
+    Int32 size = new Int32();
+    int recv = readI32(in, size);
+    byte[] buf = new byte[size.get()];
+    in.readAll(buf, 0, size.get());
     s.value = new String(buf);
-    return recv + size.toInt();
+    return recv + size.get();
   }
 }
diff --git a/lib/java/src/protocol/TField.java b/lib/java/src/protocol/TField.java
index 83f1fc3..d758c68 100644
--- a/lib/java/src/protocol/TField.java
+++ b/lib/java/src/protocol/TField.java
@@ -11,10 +11,10 @@
   public TField() {}
 
   public TField(String n, TType t, int i) {
-    this(n, t, new UInt32(i));
+    this(n, t, new Int32(i));
   }
 
-  public TField(String n, TType t, UInt32 i) {
+  public TField(String n, TType t, Int32 i) {
     name = n;
     type = t;
     id = i;
@@ -22,5 +22,5 @@
 
   public String name = "";
   public TType  type = TType.STOP;
-  public UInt32 id = new UInt32();
+  public Int32 id = new Int32();
 }
diff --git a/lib/java/src/protocol/TList.java b/lib/java/src/protocol/TList.java
index 6eac06b..ff76ffd 100644
--- a/lib/java/src/protocol/TList.java
+++ b/lib/java/src/protocol/TList.java
@@ -11,14 +11,14 @@
   public TList() {}
   
   public TList(TType t, int s) {
-    this(t, new UInt32(s));
+    this(t, new Int32(s));
   }
 
-  public TList(TType t, UInt32 s) {
+  public TList(TType t, Int32 s) {
     elemType = t;
     size = s;
   }
 
   public TType  elemType = TType.STOP;
-  public UInt32 size = new UInt32();
+  public Int32 size = new Int32();
 }
diff --git a/lib/java/src/protocol/TMap.java b/lib/java/src/protocol/TMap.java
index 84eb468..f251fa6 100644
--- a/lib/java/src/protocol/TMap.java
+++ b/lib/java/src/protocol/TMap.java
@@ -11,10 +11,10 @@
   public TMap() {}
   
   public TMap(TType k, TType v, int s) {
-    this(k, v, new UInt32(s));
+    this(k, v, new Int32(s));
   }
 
-  public TMap(TType k, TType v, UInt32 s) {
+  public TMap(TType k, TType v, Int32 s) {
     keyType = k;
     valueType = v;
     size = s;
@@ -22,5 +22,5 @@
 
   public TType  keyType = TType.STOP;
   public TType  valueType = TType.STOP;
-  public UInt32 size = new UInt32();;
+  public Int32 size = new Int32();;
 }
diff --git a/lib/java/src/protocol/TSet.java b/lib/java/src/protocol/TSet.java
index e0dcf76..fa6e24d 100644
--- a/lib/java/src/protocol/TSet.java
+++ b/lib/java/src/protocol/TSet.java
@@ -11,14 +11,14 @@
   public TSet() {}
 
   public TSet(TType t, int s) {
-    this(t, new UInt32(s));
+    this(t, new Int32(s));
   }
 
-  public TSet(TType t, UInt32 s) {
+  public TSet(TType t, Int32 s) {
     elemType = t;
     size = s;
   }
 
   public TType  elemType = TType.STOP;
-  public UInt32 size = new UInt32();
+  public Int32 size = new Int32();
 }