diff --git a/java_gen/pre-written/src/main/java/org/openflow/types/IPv4WithMask.java b/java_gen/pre-written/src/main/java/org/openflow/types/IPv4WithMask.java
index c24c4fd..0a1a6d3 100644
--- a/java_gen/pre-written/src/main/java/org/openflow/types/IPv4WithMask.java
+++ b/java_gen/pre-written/src/main/java/org/openflow/types/IPv4WithMask.java
@@ -36,7 +36,7 @@
         return res.toString();
     }
     
-    public static OFValueType<?> ofPossiblyMasked(final String string) {
+    public static IPv4WithMask of(final String string) {
         int slashPos;
         String ip = string;
         int maskBits = 0;
@@ -72,7 +72,7 @@
             return IPv4WithMask.of(ipv4, maskAddress);
         } else if (maskBits == 0) {
             // No mask
-            return ipv4;
+            return IPv4WithMask.of(ipv4, IPv4.of(0xFFFFFFFF));
         } else {
             // With mask
             int mask = (-1) << (32 - maskBits);
diff --git a/java_gen/pre-written/src/main/java/org/openflow/types/IPv6WithMask.java b/java_gen/pre-written/src/main/java/org/openflow/types/IPv6WithMask.java
index 72319e3..453507a 100644
--- a/java_gen/pre-written/src/main/java/org/openflow/types/IPv6WithMask.java
+++ b/java_gen/pre-written/src/main/java/org/openflow/types/IPv6WithMask.java
@@ -31,7 +31,7 @@
         return res.toString();
     }
     
-    public static OFValueType<?> ofPossiblyMasked(final String string) {
+    public static IPv6WithMask of(final String string) {
         int slashPos;
         String ip = string;
         int maskBits = 0;
@@ -67,7 +67,7 @@
             return IPv6WithMask.of(ipv6, maskAddress);
         } else if (maskBits == 0) {
             // No mask
-            return ipv6;
+            return IPv6WithMask.of(ipv6, IPv6.of(0xFFFFFFFFFFFFFFFFl, 0xFFFFFFFFFFFFFFFFl));
         } else {
             // With mask
             BigInteger mask = BigInteger.ONE.negate().shiftLeft(128 - maskBits);
diff --git a/java_gen/pre-written/src/main/java/org/openflow/types/OFMetadata.java b/java_gen/pre-written/src/main/java/org/openflow/types/OFMetadata.java
new file mode 100644
index 0000000..83d02da
--- /dev/null
+++ b/java_gen/pre-written/src/main/java/org/openflow/types/OFMetadata.java
@@ -0,0 +1,34 @@
+package org.openflow.types;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+
+public class OFMetadata extends U64 implements OFValueType<OFMetadata> {
+    
+    private static int LENGTH = 8;
+
+    protected OFMetadata(long raw) {
+        super(raw);
+    }
+
+    public static OFMetadata of(long raw) {
+        return new OFMetadata(raw);
+    }
+    
+    public static OFMetadata read8Bytes(ChannelBuffer cb) {
+        return OFMetadata.of(cb.readLong());
+    }
+    
+    public void write8Bytes(ChannelBuffer cb) {
+        cb.writeLong(super.getValue());
+    }
+
+    @Override
+    public int getLength() {
+        return LENGTH;
+    }
+
+    @Override
+    public OFMetadata applyMask(OFMetadata mask) {
+        return OFMetadata.of(this.getValue() & mask.getValue());
+    }
+}
diff --git a/java_gen/pre-written/src/main/java/org/openflow/types/U64.java b/java_gen/pre-written/src/main/java/org/openflow/types/U64.java
index 750398f..7871445 100644
--- a/java_gen/pre-written/src/main/java/org/openflow/types/U64.java
+++ b/java_gen/pre-written/src/main/java/org/openflow/types/U64.java
@@ -24,7 +24,7 @@
 
     private final long raw;
 
-    private U64(final long raw) {
+    protected U64(final long raw) {
         this.raw = raw;
     }
 
diff --git a/java_gen/pre-written/src/main/java/org/openflow/types/VlanVid.java b/java_gen/pre-written/src/main/java/org/openflow/types/VlanVid.java
index ca2c3c2..e36a5dd 100644
--- a/java_gen/pre-written/src/main/java/org/openflow/types/VlanVid.java
+++ b/java_gen/pre-written/src/main/java/org/openflow/types/VlanVid.java
@@ -70,7 +70,7 @@
         c.writeShort(this.vid);
     }
 
-    public VlanVid read2Bytes(ChannelBuffer c) throws OFParseError {
+    public static VlanVid read2Bytes(ChannelBuffer c) throws OFParseError {
         return VlanVid.of(c.readShort());
     }