javax.swing
Class KeyStroke

java.lang.Object sample code for java.lang.Object definition code for java.lang.Object 
  extended by java.awt.AWTKeyStroke sample code for java.awt.AWTKeyStroke definition code for java.awt.AWTKeyStroke 
      extended by javax.swing.KeyStroke
All Implemented Interfaces:
Serializable sample code for java.io.Serializable definition code for java.io.Serializable

public class KeyStroke
extends AWTKeyStroke sample code for java.awt.AWTKeyStroke definition code for java.awt.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 sample code for java.beans.XMLEncoder definition code for java.beans.XMLEncoder .

See Also:
Keymap sample code for javax.swing.text.Keymap definition code for javax.swing.text.Keymap , getKeyStroke(char) sample code for javax.swing.KeyStroke.getKeyStroke(char) definition code for javax.swing.KeyStroke.getKeyStroke(char) , Serialized Form

Method Summary
static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.KeyStroke getKeyStroke sample code for javax.swing.KeyStroke.getKeyStroke(char) definition code for javax.swing.KeyStroke.getKeyStroke(char) (char keyChar)
          Returns a shared instance of a KeyStroke that represents a KEY_TYPED event for the specified character.
static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.KeyStroke getKeyStroke sample code for javax.swing.KeyStroke.getKeyStroke(java.lang.Character, int) definition code for javax.swing.KeyStroke.getKeyStroke(java.lang.Character, int) (Character sample code for java.lang.Character definition code for java.lang.Character  keyChar, int modifiers)
          Returns a shared instance of a KeyStroke, given a Character object and a set of modifiers.
static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.KeyStroke getKeyStroke sample code for javax.swing.KeyStroke.getKeyStroke(char, boolean) definition code for javax.swing.KeyStroke.getKeyStroke(char, boolean) (char keyChar, boolean onKeyRelease)
          Deprecated. use getKeyStroke(char)
static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.KeyStroke getKeyStroke sample code for javax.swing.KeyStroke.getKeyStroke(int, int) definition code for javax.swing.KeyStroke.getKeyStroke(int, int) (int keyCode, int modifiers)
          Returns a shared instance of a KeyStroke, given a numeric key code and a set of modifiers.
static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.KeyStroke getKeyStroke sample code for javax.swing.KeyStroke.getKeyStroke(int, int, boolean) definition code for javax.swing.KeyStroke.getKeyStroke(int, int, boolean) (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 sample code for javax.swing.KeyStroke definition code for javax.swing.KeyStroke getKeyStroke sample code for javax.swing.KeyStroke.getKeyStroke(java.lang.String) definition code for javax.swing.KeyStroke.getKeyStroke(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  s)
          Parses a string and returns a KeyStroke.
static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.KeyStroke getKeyStrokeForEvent sample code for javax.swing.KeyStroke.getKeyStrokeForEvent(java.awt.event.KeyEvent) definition code for javax.swing.KeyStroke.getKeyStrokeForEvent(java.awt.event.KeyEvent) (KeyEvent sample code for java.awt.event.KeyEvent definition code for java.awt.event.KeyEvent  anEvent)
          Returns a KeyStroke which represents the stroke which generated a given KeyEvent.
 
Methods inherited from class java.awt.AWTKeyStroke sample code for java.awt.AWTKeyStroke definition code for java.awt.AWTKeyStroke
equals sample code for java.awt.AWTKeyStroke.equals(java.lang.Object) definition code for java.awt.AWTKeyStroke.equals(java.lang.Object) , getAWTKeyStroke sample code for java.awt.AWTKeyStroke.getAWTKeyStroke(char) definition code for java.awt.AWTKeyStroke.getAWTKeyStroke(char) , getAWTKeyStroke sample code for java.awt.AWTKeyStroke.getAWTKeyStroke(java.lang.Character, int) definition code for java.awt.AWTKeyStroke.getAWTKeyStroke(java.lang.Character, int) , getAWTKeyStroke sample code for java.awt.AWTKeyStroke.getAWTKeyStroke(int, int) definition code for java.awt.AWTKeyStroke.getAWTKeyStroke(int, int) , getAWTKeyStroke sample code for java.awt.AWTKeyStroke.getAWTKeyStroke(int, int, boolean) definition code for java.awt.AWTKeyStroke.getAWTKeyStroke(int, int, boolean) , getAWTKeyStroke sample code for java.awt.AWTKeyStroke.getAWTKeyStroke(java.lang.String) definition code for java.awt.AWTKeyStroke.getAWTKeyStroke(java.lang.String) , getAWTKeyStrokeForEvent sample code for java.awt.AWTKeyStroke.getAWTKeyStrokeForEvent(java.awt.event.KeyEvent) definition code for java.awt.AWTKeyStroke.getAWTKeyStrokeForEvent(java.awt.event.KeyEvent) , getKeyChar sample code for java.awt.AWTKeyStroke.getKeyChar() definition code for java.awt.AWTKeyStroke.getKeyChar() , getKeyCode sample code for java.awt.AWTKeyStroke.getKeyCode() definition code for java.awt.AWTKeyStroke.getKeyCode() , getKeyEventType sample code for java.awt.AWTKeyStroke.getKeyEventType() definition code for java.awt.AWTKeyStroke.getKeyEventType() , getModifiers sample code for java.awt.AWTKeyStroke.getModifiers() definition code for java.awt.AWTKeyStroke.getModifiers() , hashCode sample code for java.awt.AWTKeyStroke.hashCode() definition code for java.awt.AWTKeyStroke.hashCode() , isOnKeyRelease sample code for java.awt.AWTKeyStroke.isOnKeyRelease() definition code for java.awt.AWTKeyStroke.isOnKeyRelease() , readResolve sample code for java.awt.AWTKeyStroke.readResolve() definition code for java.awt.AWTKeyStroke.readResolve() , registerSubclass sample code for java.awt.AWTKeyStroke.registerSubclass(java.lang.Class) definition code for java.awt.AWTKeyStroke.registerSubclass(java.lang.Class) , toString sample code for java.awt.AWTKeyStroke.toString() definition code for java.awt.AWTKeyStroke.toString()
 
Methods inherited from class java.lang.Object sample code for java.lang.Object definition code for java.lang.Object
clone sample code for java.lang.Object.clone() definition code for java.lang.Object.clone() , finalize sample code for java.lang.Object.finalize() definition code for java.lang.Object.finalize() , getClass sample code for java.lang.Object.getClass() definition code for java.lang.Object.getClass() , notify sample code for java.lang.Object.notify() definition code for java.lang.Object.notify() , notifyAll sample code for java.lang.Object.notifyAll() definition code for java.lang.Object.notifyAll() , wait sample code for java.lang.Object.wait() definition code for java.lang.Object.wait() , wait sample code for java.lang.Object.wait(long) definition code for java.lang.Object.wait(long) , wait sample code for java.lang.Object.wait(long, int) definition code for java.lang.Object.wait(long, int)
 

Method Detail

getKeyStroke sample code for javax.swing.KeyStroke.getKeyStroke(char) definition code for javax.swing.KeyStroke.getKeyStroke(char)

public static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.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 sample code for javax.swing.KeyStroke.getKeyStroke(char, boolean) definition code for javax.swing.KeyStroke.getKeyStroke(char, boolean)

@Deprecated
public static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.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 sample code for javax.swing.KeyStroke.getKeyStroke(java.lang.Character, int) definition code for javax.swing.KeyStroke.getKeyStroke(java.lang.Character, int)

public static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.KeyStroke  getKeyStroke(Character sample code for java.lang.Character definition code for java.lang.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: 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 sample code for java.lang.IllegalArgumentException definition code for java.lang.IllegalArgumentException - if keyChar is null
Since:
1.3
See Also:
InputEvent sample code for java.awt.event.InputEvent definition code for java.awt.event.InputEvent

getKeyStroke sample code for javax.swing.KeyStroke.getKeyStroke(int, int, boolean) definition code for javax.swing.KeyStroke.getKeyStroke(int, int, boolean)

public static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.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:

The modifiers consist of any combination of: 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 sample code for java.awt.event.KeyEvent definition code for java.awt.event.KeyEvent , InputEvent sample code for java.awt.event.InputEvent definition code for java.awt.event.InputEvent

getKeyStroke sample code for javax.swing.KeyStroke.getKeyStroke(int, int) definition code for javax.swing.KeyStroke.getKeyStroke(int, int)

public static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.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:

The modifiers consist of any combination of: 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 sample code for java.awt.event.KeyEvent definition code for java.awt.event.KeyEvent , InputEvent sample code for java.awt.event.InputEvent definition code for java.awt.event.InputEvent

getKeyStrokeForEvent sample code for javax.swing.KeyStroke.getKeyStrokeForEvent(java.awt.event.KeyEvent) definition code for javax.swing.KeyStroke.getKeyStrokeForEvent(java.awt.event.KeyEvent)

public static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.KeyStroke  getKeyStrokeForEvent(KeyEvent sample code for java.awt.event.KeyEvent definition code for java.awt.event.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 sample code for java.lang.NullPointerException definition code for java.lang.NullPointerException - if anEvent is null

getKeyStroke sample code for javax.swing.KeyStroke.getKeyStroke(java.lang.String) definition code for javax.swing.KeyStroke.getKeyStroke(java.lang.String)

public static KeyStroke sample code for javax.swing.KeyStroke definition code for javax.swing.KeyStroke  getKeyStroke(String sample code for java.lang.String definition code for java.lang.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