Post method invocation interception with Cglib

Question

I was wondering if it is possible to intercept a method after the invocation of the target method? For example as you can see below:

@CleanUp
public void doSomething{
...
}

I want to be able to intercept the method after the method invocation. In above sample, I will do common clean up after the invocation of method.

Answer 1

If you use the standard CGLIB Enhancer you can choose whether you want to execute code before or after the method being proxied is invoked. For instance:

MyClass proxy = (List<String>)Enhancer.create(MyClass.class, new MyInvocationHandler());
proxy.aMethodToInvoke();
.
.
.
class MyInvocationHandler implements MethodInterceptor {
    public Object intercept(Object obj, Method method, Object[] args, MethodProxy proxy) throws Throwable {
        System.out.println("Before we invoke the method");
        Object retObj = proxy.invoke(obj, args);
        System.out.println("After we invoke the method");
        return retObj;
    }
}

So anything after the proxy.invoke call will be code which executes after the method being proxy has been called and has returned.