Java 6 Illuminated: An Active Learning Approach, 2nd Edition

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If you do not register a lis-

tener on a component,the

component will not fire an

event.Thus,the event han-

dler will not execute when

the user interacts with the

component.

COMMON ERROR

TRAP

844 CHAPTER 12 Graphical User Interfaces

presses the Enter key, the component that is in focus will fire an action

event and our actionPerformed method will be executed.

We implement the actionPerformed method at lines 69–82. Because we

defined this event handler as a private inner class, the actionPerformed

method can directly access the id and password fields. At lines 71–72, we test

if the ID and password entered by the user are correct.

As shown in Table 12.9, the ...