diff --git a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/U8.java b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/U8.java
index c644599..17191af 100644
--- a/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/U8.java
+++ b/java_gen/pre-written/src/main/java/org/projectfloodlight/openflow/types/U8.java
@@ -62,7 +62,7 @@
 
     @Override
     public String toString() {
-        return "" + f(raw);
+        return String.format("0x%02x", raw);
     }
 
     @Override