mnrz [http://community.jboss.org/people/mnrz] created the discussion "Adding interface to an existing class" To view the discussion, visit: http://community.jboss.org/message/608679#608679 -------------------------------------------------------------- Hi I have a class which is in legacy system and we cannot change the class. I need to create a java proxy for that class but this is a class without interface. So I have created an interface and write the following code to add this interface to that class at runtime but the class.getInterfaces() method still returns no interface! -- public class Main {     public static void main(String[] args) throws Exception {         //@SuppressWarnings("rawtypes")         createInterface();         AnAbstractClass instance = new AClassFromAbstract();//instance.getClass().getInterfaces()         Object proxy = Proxy.newProxyInstance(ProxyIntAnAbstractClass.class.getClassLoader(),                 new Class[] {ProxyIntAnAbstractClass.class},                 new MyInvocationHandler(instance));         ProxyIntAnAbstractClass instance2 = (ProxyIntAnAbstractClass) proxy;         instance2.doSomething();         instance2.doSomethingElse();     }     public static Class createInterface() throws Exception{         ClassPool pool = ClassPool.getDefault();         ClassPath cp = new ClassClassPath(AnAbstractClass.class);         pool.insertClassPath(cp);         pool.importPackage("com.macquarie.test.proxy");         CtClass myinterface = pool.get("com.mmm.test.proxy.ProxyIntAnAbstractClass");         CtClass tclass = pool.getCtClass("com.mmm.test.proxy.AnAbstractClass");         tclass.setInterfaces(new CtClass[] {myinterface});         tclass.rebuildClassFile();         tclass.detach();         return myinterface.toClass();     } } -- When I execute this code, since the ProxyIntAnAbstractClass is not interface of AnAbstractClass, InvocationHandler complains that the object is not an instance of declaring class Can you please help me on this? -------------------------------------------------------------- Reply to this message by going to Community [http://community.jboss.org/message/608679#608679] Start a new discussion in Javassist at Community [http://community.jboss.org/choose-container!input.jspa?contentType=1&...]