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/ICMPv4Code.java b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/ICMPv4Code.java
index c66486f..6466eee 100644
--- a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/ICMPv4Code.java
+++ b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/ICMPv4Code.java
@@ -2,6 +2,7 @@
 
 import org.jboss.netty.buffer.ChannelBuffer;
 
+import com.google.common.hash.PrimitiveSink;
 import com.google.common.primitives.Shorts;
 
 /**
@@ -84,4 +85,9 @@
     public int compareTo(ICMPv4Code o) {
         return Shorts.compare(code, o.code);
     }
+
+    @Override
+    public void putTo(PrimitiveSink sink) {
+        sink.putShort(code);
+    }
 }