java_gen: add support for object hashing via the guava hash API
diff --git a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/U32.java b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/U32.java
index daf5fa6..9fafc30 100644
--- a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/U32.java
+++ b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/U32.java
@@ -22,6 +22,7 @@
 import org.projectfloodlight.openflow.protocol.OFMessageReader;
 import org.projectfloodlight.openflow.protocol.Writeable;
 
+import com.google.common.hash.PrimitiveSink;
 import com.google.common.primitives.UnsignedInts;
 
 public class U32 implements Writeable, OFValueType<U32> {
@@ -117,4 +118,7 @@
         return UnsignedInts.compare(raw, o.raw);
     }
 
-}
+    @Override
+    public void putTo(PrimitiveSink sink) {
+        sink.putInt(raw);
+    }}