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/ICMPv4Type.java b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/ICMPv4Type.java
index 594aaec..9768aee 100644
--- a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/ICMPv4Type.java
+++ b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/ICMPv4Type.java
@@ -2,6 +2,7 @@
 
 import org.jboss.netty.buffer.ChannelBuffer;
 
+import com.google.common.hash.PrimitiveSink;
 import com.google.common.primitives.Shorts;
 
 public class ICMPv4Type implements OFValueType<ICMPv4Type> {
@@ -193,4 +194,10 @@
     public int compareTo(ICMPv4Type o) {
         return Shorts.compare(type, o.type);
     }
+
+    @Override
+    public void putTo(PrimitiveSink sink) {
+        sink.putShort(type);
+    }
+
 }