ByteBuddy intercept the calls toward specific class instances inside the bytecode of a method

Question

I have a class A with a method m() and a class B with a method n(). In AI have a field b of type B. In m() there is at some point a call to bn(). I need to change the code of A with ByteBuddy in order to do some action before and after the bn() call. I need some advice/tips/hint to attack the problem.

Thanks in advance,

Radu

Answer 1

You can only do this in Byte Buddy by writing custom byte code using the underlying ASM API. Byte Buddy does not offer any high-level constructs to alter any code within a method.

The API is exposed by registering an AsmVisitorWrapper.

Alternatively, you could create a subclass of Bn() where you add this interception logic and set it as the field of A. This would however affect all invokations via A.