The ItemListener Interface:

This interface declares the itemStateChanged ( ) method which is invoked when the state of an item modifies. It common form is display here:

Syntax :  Void itemStateChanged (ItemEvent ie)

The KeyListener Interface:

This interface declares three methods. The KeyPressed ( ) and KeyReleased ( ) methods are invoked whenever a key  is  pressed  and  released  correspondingly. A KeyTyped ( ) methods is invoked when a character has been entered.

For instance, if a user presses and releases the key, three events are produced in sequence, key pressed, typed and released. Two key events are generated in sequence key pressed and released if a user presses and releases the Home key.

The common forms of these methods are display here:

Syntax:  void keyPressed (keyEvent ke)

Syntax:  void keyReleased (keyEvent ke)

Syntax:  void keyTyped (keyEvent ke)