diff --git a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/IPv6AddressWithMask.java b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/IPv6AddressWithMask.java
index dcaa0b6..f918d1c 100644
--- a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/IPv6AddressWithMask.java
+++ b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/IPv6AddressWithMask.java
@@ -3,13 +3,20 @@
 import java.math.BigInteger;
 import java.util.Arrays;
 
-public class IPv6AddressWithMask extends Masked<IPv6Address> {
+import org.projectfloodlight.openflow.types.IPAddress.IpVersion;
+
+public class IPv6AddressWithMask extends IPAddressWithMask<IPv6Address> {
     public final static IPv6AddressWithMask NONE = of(IPv6Address.NONE, IPv6Address.NONE);
 
     private IPv6AddressWithMask(IPv6Address value, IPv6Address mask) {
         super(value, mask);
     }
 
+    @Override
+    public IpVersion getIpVersion() {
+        return IpVersion.IPv6;
+    }
+
     public static IPv6AddressWithMask of(IPv6Address value, IPv6Address mask) {
         return new IPv6AddressWithMask(value, mask);
     }