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## javax.swing
Class KeyStroke

    java.lang.Object
      java.awt.AWTKeyStroke
          javax.swing.KeyStroke

All Implemented Interfaces:
  Serializable

    public class KeyStroke

extends AWTKeyStroke

A KeyStroke represents a key action on the keyboard, or equivalent input device. KeyStrokes can correspond to only a press or release of a particular key, just as KEY_PRESSED and KEY_RELEASED KeyEvents do; alternately, they can correspond to typing a specific Java character, just as KEY_TYPED KeyEvents do. In all cases, KeyStrokes can specify modifiers (alt, shift, control, meta, or a combination thereof) which must be present during the action for an exact match.

KeyStrokes are used to define high-level (semantic) action events. Instead of trapping every keystroke and throwing away the ones you are not interested in, those keystrokes you care about automatically initiate actions on the Components with which they are registered.

KeyStrokes are immutable, and are intended to be unique. Client code cannot create a KeyStroke; a variant of `getKeyStroke` must be used instead. These factory methods allow the KeyStroke implementation to cache and share instances efficiently.

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeansTM has been added to the `java.beans` package. Please see `XMLEncoder`.

See Also:
  `Keymap`, `getKeyStroke(char)`

Method Summary
`static KeyStroke` | `getKeyStroke(char keyChar)` Returns a shared instance of a `KeyStroke` that represents a `KEY_TYPED` event for the specified character.
`static KeyStroke` | `getKeyStroke(Character keyChar, int modifiers)` Returns a shared instance of a KeyStroke, given a Character object and a set of modifiers.
`static KeyStroke` | `getKeyStroke(char keyChar, boolean onKeyRelease)` Deprecated. use getKeyStroke(char)
`static KeyStroke` | `getKeyStroke(int keyCode, int modifiers)` Returns a shared instance of a KeyStroke, given a numeric key code and a set of modifiers.
`static KeyStroke` | `getKeyStroke(int keyCode, int modifiers, boolean onKeyRelease)` Returns a shared instance of a KeyStroke, given a numeric key code and a set of modifiers, specifying whether the key is activated when it is pressed or released.
`static KeyStroke` | `getKeyStroke(String s)` Parses a string and returns a `KeyStroke`.
`static KeyStroke` | `getKeyStrokeForEvent(KeyEvent anEvent)` Returns a KeyStroke which represents the stroke which generated a given KeyEvent.

Methods inherited from class java.awt.AWTKeyStroke
`equals, getAWTKeyStroke, getAWTKeyStroke, getAWTKeyStroke, getAWTKeyStroke, getAWTKeyStroke, getAWTKeyStrokeForEvent, getKeyChar, getKeyCode, getKeyEventType, getModifiers, hashCode, isOnKeyRelease, readResolve, registerSubclass, toString`

Methods inherited from class java.lang.Object
`clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

Method Detail

### getKeyStroke

    public static KeyStroke getKeyStroke(char keyChar)

  Returns a shared instance of a `KeyStroke` that represents a `KEY_TYPED` event for the specified character.

  Parameters:
    `keyChar` - the character value for a keyboard key
  Returns:
    a KeyStroke object for that key

### getKeyStroke

    @Deprecated
    public static KeyStroke getKeyStroke(char keyChar,
                                                    boolean onKeyRelease)

  Deprecated. use getKeyStroke(char)

  Returns an instance of a KeyStroke, specifying whether the key is considered to be activated when it is pressed or released. Unlike all other factory methods in this class, the instances returned by this method are not necessarily cached or shared.

  Parameters:
    `keyChar` - the character value for a keyboard key
    `onKeyRelease` - `true` if this KeyStroke corresponds to a key release; `false` otherwise.
  Returns:
    a KeyStroke object for that key

### getKeyStroke

    public static KeyStroke getKeyStroke(Character keyChar,
                                         int modifiers)

  Returns a shared instance of a KeyStroke, given a Character object and a set of modifiers. Note that the first parameter is of type Character rather than char. This is to avoid inadvertent clashes with calls to `getKeyStroke(int keyCode, int modifiers)`. The modifiers consist of any combination of:
  - java.awt.event.InputEvent.SHIFT_MASK (1)
  - java.awt.event.InputEvent.CTRL_MASK (2)
  - java.awt.event.InputEvent.META_MASK (4)
  - java.awt.event.InputEvent.ALT_MASK (8)
  Since these numbers are all different powers of two, any combination of them is an integer in which each bit represents a different modifier key. Use 0 to specify no modifiers.

  Parameters:
    `keyChar` - the Character object for a keyboard character
    `modifiers` - a bitwise-ored combination of any modifiers
  Returns:
    an KeyStroke object for that key
  Throws:
    `IllegalArgumentException` - if keyChar is null
  Since:
    1.3
  See Also:
    `InputEvent`

### getKeyStroke

    public static KeyStroke getKeyStroke(int keyCode,
                                         int modifiers,
                                         boolean onKeyRelease)

  Returns a shared instance of a KeyStroke, given a numeric key code and a set of modifiers, specifying whether the key is activated when it is pressed or released.

  The "virtual key" constants defined in java.awt.event.KeyEvent can be used to specify the key code. For example:

  - java.awt.event.KeyEvent.VK_ENTER
  - java.awt.event.KeyEvent.VK_TAB
  - java.awt.event.KeyEvent.VK_SPACE
  The modifiers consist of any combination of:
  - java.awt.event.InputEvent.SHIFT_MASK (1)
  - java.awt.event.InputEvent.CTRL_MASK (2)
  - java.awt.event.InputEvent.META_MASK (4)
  - java.awt.event.InputEvent.ALT_MASK (8)
  Since these numbers are all different powers of two, any combination of them is an integer in which each bit represents a different modifier key. Use 0 to specify no modifiers.

  Parameters:
    `keyCode` - an int specifying the numeric code for a keyboard key
    `modifiers` - a bitwise-ored combination of any modifiers
    `onKeyRelease` - `true` if the KeyStroke should represent a key release; `false` otherwise.
  Returns:
    a KeyStroke object for that key
  See Also:
    `KeyEvent`, `InputEvent`

### getKeyStroke

    public static KeyStroke getKeyStroke(int keyCode,
                                         int modifiers)

  Returns a shared instance of a KeyStroke, given a numeric key code and a set of modifiers. The returned KeyStroke will correspond to a key press.

  The "virtual key" constants defined in java.awt.event.KeyEvent can be used to specify the key code. For example:

  - java.awt.event.KeyEvent.VK_ENTER
  - java.awt.event.KeyEvent.VK_TAB
  - java.awt.event.KeyEvent.VK_SPACE
  The modifiers consist of any combination of:
  - java.awt.event.InputEvent.SHIFT_MASK (1)
  - java.awt.event.InputEvent.CTRL_MASK (2)
  - java.awt.event.InputEvent.META_MASK (4)
  - java.awt.event.InputEvent.ALT_MASK (8)
  Since these numbers are all different powers of two, any combination of them is an integer in which each bit represents a different modifier key. Use 0 to specify no modifiers.

  Parameters:
    `keyCode` - an int specifying the numeric code for a keyboard key
    `modifiers` - a bitwise-ored combination of any modifiers
  Returns:
    a KeyStroke object for that key
  See Also:
    `KeyEvent`, `InputEvent`

### getKeyStrokeForEvent

    public static KeyStroke getKeyStrokeForEvent(KeyEvent anEvent)

  Returns a KeyStroke which represents the stroke which generated a given KeyEvent.

  This method obtains the keyChar from a KeyTyped event, and the keyCode from a KeyPressed or KeyReleased event. The KeyEvent modifiers are obtained for all three types of KeyEvent.

  Parameters:
    `anEvent` - the KeyEvent from which to obtain the KeyStroke
  Returns:
    the KeyStroke that precipitated the event
  Throws:
    `NullPointerException` - if `anEvent` is null

### getKeyStroke

    public static KeyStroke getKeyStroke(String s)

  Parses a string and returns a `KeyStroke`. The string must have the following syntax:

          <modifiers>* (<typedID> | <pressedReleasedID>)

          modifiers := shift | control | ctrl | meta | alt | altGraph
          typedID := typed <typedKey>
          typedKey := string of length 1 giving Unicode character.
          pressedReleasedID := (pressed | released) key
          key := KeyEvent key code name, i.e. the name following "VK_".

  If typed, pressed or released is not specified, pressed is assumed. Here are some examples:

           "INSERT" => getKeyStroke(KeyEvent.VK_INSERT, 0);
           "control DELETE" => getKeyStroke(KeyEvent.VK_DELETE, InputEvent.CTRL_MASK);
           "alt shift X" => getKeyStroke(KeyEvent.VK_X, InputEvent.ALT_MASK | InputEvent.SHIFT_MASK);
           "alt shift released X" => getKeyStroke(KeyEvent.VK_X, InputEvent.ALT_MASK | InputEvent.SHIFT_MASK, true);
           "typed a" => getKeyStroke('a');

  In order to maintain backward-compatibility, specifying a null String, or a String which is formatted incorrectly, returns null.

  Parameters:
    `s` - a String formatted as described above
  Returns:
    a KeyStroke object for that String, or null if the specified String is null, or is formatted incorrectly

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For further API reference and developer documentation, see Java 2 SDK SE Developer Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.

Copyright 2004 Sun Microsystems, Inc. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.