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I'm using the asm library to perform some Java bytecode modification - specifically to modify my classes to implement a new interface and associated methods. My current approach is using the core asm API via a javaagent. I'd like to keep this dynamic approach as opposed to statically modifying .class files. At a higher level, my problem is that if I choose to modify class A, which extends from B, I also need to modify B. (Given my understanding of how classes are loaded in the JVM, I believe that class B will always be handed to a transformer before class A. (Please correct me if I'm wrong). Given that assumption, I'm thinking that I then need to go back and retransform B. My approach is captured in this bit of code: public byte[] transform(ClassLoader l, String name, Class<?> clazz, ProtectionDomain d, byte[] b) { throws IllegalClassFormatException { // **1** System.out.println("--->>> " + name); if (interestingClass(name)) { try { ClassReader cr = new ClassReader(b); ClassWriter cw = new ClassWriter(cr, ClassWriter.COMPUTE_MAXS | ClassWriter.COMPUTE_FRAMES); PyClassVisitorAdapter pv = new PyClassVisitorAdapter(cw, name); cr.accept(pv, 0); // **2** Retrieve the superclass and try to transform that if (! "Ljava/lang/Object;".equals(pv.getSuperName())) { String cName = classJvmToCanonical(pv.getSuperName()); Class[] classes = inst.getAllLoadedClasses(); for (Class c : classes) { if (c.getName().equals(cName)) { inst.retransformClasses(c); break; } } } // Dump the transformed class ClassReader cr2 = new ClassReader(cw.toByteArray()); ClassWriter cw2 = new ClassWriter(cr2, 0); TraceClassVisitor tcv = new TraceCl

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