What is this java.awt.event error?

public void actionPerformed(ActionEvent e) {
	String cmd = e.getActionCommand();
	String name;

code...

if(cmd.equals("Play")) {
		name = field.getText();
		card = getCard(name);

		if(card != null) {
			if(rules.zoneHasCard(card, rules.hand)) {
				display.updateStatusMessage(rules.play(card));
				field.setText("");
				display.updateHand(rules.zoneList("hand"));
				display.updateDiscard(rules.zoneList("Discard")); // This is the error here! The discard Zone was empty!
			}
			else {
				field.setText("You do not have " + card.getName());
				field.selectAll();
			}
		}
		else {
			field.setText("That cardname is unused");
			field.selectAll();
		}
	}
}

public void actionPerformed(ActionEvent e) {
        String cmd = e.getActionCommand();
        String name;

// more code...
}

System.out.println("field = " + field);
System.out.println("rules = " + rules);
System.out.println("display = " + display);