Is ActionListener an example of Delegation pattern?

Question

In my college days, I never realized what patterns were there in the Java API. Now at work I came across Delegation pattern in Objective C n Cocoa on iOS where one screen sets itself as a delegate on coming screen so that that screen can pass some message to that delegate and it can take some action when it comes back to the previous screen.

I realize that I use to do something similar with when I used to pass "this" as as ActionListener [by implementing the interface] to a JButton and it would automatically call actionPerformed implemented by me in this class and thus I could change any instance data in my JFrame class.

So Is ActionListener an example of Delegate If I am correct ?

EDIT: As correctly mentioned below, It is Observer pattern. We dont set ActionListener we add one. Thus there can be many Listeners to that action.

Answer 1

ActionListener is an example of the observer pattern. You register observers (or listeners) on a component that get called when a specific event occurs.