Can change static methods at run time using java Instrumentation?

Question

I need to change static methods inside third party libraries. I have done transforming instance method but not sure same thing applies to static methods.

I have several static methods called myMethod inside MyClass.java. I need to change implementation of myMethod during run time. Basically I extended ClassFileTransformer and overrode byte[] transform method something like bellow. This worked for instance methods but I am not sure if I can do the same for static methods.

@Override
public byte[] transform(ClassLoader loader, String className, Class<?> classBeingRedefined,
                        ProtectionDomain protectionDomain, byte[] classfileBuffer)
    throws IllegalClassFormatException {

}

Answer 1

Yes, of course this is possible. You can change the entire class file. For most VMs, you can only change the implementation of the method but not its signature. If a method is static or not does not matter.