# Class KeyAdapter

java.lang.Object
java.awt.event.KeyAdapter

All Implemented Interfaces:
  `KeyListener, EventListener`

Direct Known Subclasses:
  `BasicComboBoxUI.KeyHandler, BasicComboPopup.InvocationKeyHandler, BasicTreeUI.KeyHandler`

public abstract class KeyAdapter extends Object implements KeyListener
An abstract adapter class for receiving keyboard events. The methods in this class are empty. This class exists as convenience for creating listener objects.

Extend this class to create a `KeyEvent` listener and override the methods for the events of interest. (If you implement the `KeyListener` interface, you have to define all of the methods in it. This abstract class defines null methods for them all, so you can only have to define methods for events you care about.)

Create a listener object using the extended class and then register it with a component using the component's `addKeyListener` method. When a key is pressed, released, or typed, the relevant method in the listener object is invoked, and the `KeyEvent` is passed to it.

Since:
  1.1
See Also:
  - `KeyEvent`
  - `KeyListener`
  - Tutorial: Writing a Key Listener

- ## Constructor Summary

  Constructors
  Modifier
  Constructor
  Description
  `protected`
  `KeyAdapter()`
  Constructs a `KeyAdapter`.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `keyPressed(KeyEvent e)`
  Invoked when a key has been pressed.
  `void`
  `keyReleased(KeyEvent e)`
  Invoked when a key has been released.
  `void`
  `keyTyped(KeyEvent e)`
  Invoked when a key has been typed.

  ### Methods declared in class Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`
  Modifier and Type
  Method
  Description
  `protected Object`
  `clone()`
  Creates and returns a copy of this object.
  `boolean`
  `equals(Object obj)`
  Indicates whether some other object is "equal to" this one.
  `protected void`
  `finalize()`
  Deprecated, for removal: This API element is subject to removal in a future version.
  Finalization is deprecated and subject to removal in a future release.
  `final Class<?>`
  `getClass()`
  Returns the runtime class of this `Object`.
  `int`
  `hashCode()`
  Returns a hash code value for this object.
  `final void`
  `notify()`
  Wakes up a single thread that is waiting on this object's monitor.
  `final void`
  `notifyAll()`
  Wakes up all threads that are waiting on this object's monitor.
  `String`
  `toString()`
  Returns a string representation of the object.
  `final void`
  `wait()`
  Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
  `final void`
  `wait(long timeoutMillis)`
  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
  `final void`
  `wait(long timeoutMillis, int nanos)`
  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

- ## Constructor Details

  - ### KeyAdapter

    protected KeyAdapter()
    Constructs a `KeyAdapter`.

- ## Method Details

  - ### keyTyped

    public void keyTyped(KeyEvent e)
    Invoked when a key has been typed. This event occurs when a key press is followed by a key release.
    Specified by:
      `keyTyped` in interface `KeyListener`
    Parameters:
      `e` - the event to be processed

  - ### keyPressed

    public void keyPressed(KeyEvent e)
    Invoked when a key has been pressed.
    Specified by:
      `keyPressed` in interface `KeyListener`
    Parameters:
      `e` - the event to be processed

  - ### keyReleased

    public void keyReleased(KeyEvent e)
    Invoked when a key has been released.
    Specified by:
      `keyReleased` in interface `KeyListener`
    Parameters:
      `e` - the event to be processed