I guess nobody understood the question. I guess what this guy wanted was something like this:
return new (class implements MyInterface {
@Override
public void myInterfaceMethod() { /*do something*/ }
});
because this would allow things like multiple interface implementations:
return new (class implements MyInterface, AnotherInterface {
@Override
public void myInterfaceMethod() { /*do something*/ }
@Override
public void anotherInterfaceMethod() { /*do something*/ }
});
this would be really nice indeed; but that's not allowed in Java.
What you can do is use local classes inside method blocks:
public AnotherInterface createAnotherInterface() {
class LocalClass implements MyInterface, AnotherInterface {
@Override
public void myInterfaceMethod() { /*do something*/ }
@Override
public void anotherInterfaceMethod() { /*do something*/ }
}
return new LocalClass();
}