Hi, I'm using ClassFile.renameClass as in jbossretro in order to replace instances of a class in a jar to my own class. This is what I wants to achieve: Some classes are using class A: public class A { .... } I've created a new class AA: public class AA extends A{ ....(overwrite some methods) } I want to replace the A instances with AA in the jar. In the jar I have class B as follows: public class B { .... private final A a = ....; .... } But... I cannot replace the final fields. I've looked at JBosRetro - when replacing the StringBuilder with JBossStringBuilder - they have the same bug. final field referring to StringBuilder are not replaceable. Is there a way to replace the final declaration - I'm working on the bytecode. 10x, Keren View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4222568#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...