Overriding a method in an instantiated Java object

Question

I would like to override a method in an object that\'s handed to me by a factory that I have little control over.

My specific problem is that I want to override the

Answer 1

Another proxying-related solution: you could use Aspects to override a method on a given object without subclassing it yourself. This is especially appropriate and common for logging. This example uses spring-aop.

class Example {

    final Foo foo;

    Example(Foo original) {
        AspectJProxyFactory factory = new AspectJProxyFactory();
        factory.setTarget(original);
        factory.addAspect(FooAspect.class);
        foo = (Foo) factory.getProxy();
    }

    @Aspect
    static class FooAspect {

        @Before("execution(Foo.doBar())")
        Object beforeDoBar() {
            // My own activity
        }
    }