CodeAttribute ca = method.getCodeAttribute();
Class<?> returnType = superclassMethod.getReturnType();
if (!returnType.isPrimitive()) {
ca.aconstNull();
} else if (returnType == double.class) {
ca.dconst(0);
} else if (returnType == float.class) {
ca.fconst(0);
} else if (returnType == long.class) {
ca.lconst(0);
} else if (returnType == void.class) {