How do I implement a simple undo/redo for actions in java?

I've created an XML editor and I'm stuck at the last phase: adding undo/redo functionality.

I've only got to add undo/redo for when users add elements, attributes, or text to the JTree.

I'm still quite new at this but in school today I attempted (unsuccessfully) to create two stack object []'s called undo and redo and to add the actions performed into them.

For instance, I have:

Action AddElement() {

// some code
public void actionPerformed(ActionEvent e) {

                    performElementAction();
                }
}

the performElementAction just actually adds an Element to the JTree.

I want to add a way to add this action performed to my undo stack. is there a simple way to just undo.push( the entire action performed) or something?