Class AWTKeyStroke

java.lang.Object
java.awt.AWTKeyStroke
All Implemented Interfaces:
Serializable
Direct Known Subclasses:
KeyStroke
public classAWTKeyStrokeextendsObjectimplementsSerializable
AnAWTKeyStroke represents a key action on the keyboard, or equivalent input device.AWTKeyStrokes can correspond to only a press or release of a particular key, just asKEY_PRESSED andKEY_RELEASED KeyEvents do; alternately, they can correspond to typing a specific Java character, just asKEY_TYPED KeyEvents do. In all cases,AWTKeyStrokes can specify modifiers (alt, shift, control, meta, altGraph, or a combination thereof) which must be present during the action for an exact match.

AWTKeyStrokes are immutable, and are intended to be unique. Client code should never create anAWTKeyStroke on its own, but should instead use a variant ofgetAWTKeyStroke. Client use of these factory methods allows theAWTKeyStroke implementation to cache and share instances efficiently.

Since:
1.4
See Also:

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    Constructs anAWTKeyStroke with default values.
    protected
    AWTKeyStroke(char keyChar, int keyCode, int modifiers, boolean onKeyRelease)
    Constructs anAWTKeyStroke with the specified values.

  • Method Summary

    Modifier and Type
    Method
    Description
    final boolean
    equals(Object anObject)
    Returns true if this object is identical to the specified object.
    getAWTKeyStroke(char keyChar)
    Returns a shared instance of anAWTKeyStroke that represents aKEY_TYPED event for the specified character.
    getAWTKeyStroke(int keyCode, int modifiers)
    Returns a shared instance of anAWTKeyStroke, given a numeric key code and a set of modifiers.
    getAWTKeyStroke(int keyCode, int modifiers, boolean onKeyRelease)
    Returns a shared instance of anAWTKeyStroke, given a numeric key code and a set of modifiers, specifying whether the key is activated when it is pressed or released.
    getAWTKeyStroke(Character keyChar, int modifiers)
    Returns a shared instance of anAWTKeyStroke that represents aKEY_TYPED event for the specified Character object and a set of modifiers.
    Parses a string and returns anAWTKeyStroke.
    Returns anAWTKeyStroke which represents the stroke which generated a givenKeyEvent.
    final char
    Returns the character for thisAWTKeyStroke.
    final int
    Returns the numeric key code for thisAWTKeyStroke.
    final int
    Returns the type ofKeyEvent which corresponds to thisAWTKeyStroke.
    final int
    Returns the modifier keys for thisAWTKeyStroke.
    int
    Returns a numeric value for this object that is likely to be unique, making it a good choice as the index value in a hash table.
    final boolean
    Returns whether thisAWTKeyStroke represents a key release.
    protectedObject
    Returns a cached instance ofAWTKeyStroke (or a subclass ofAWTKeyStroke) which is equal to this instance.
    protected static void
    registerSubclass(Class<?> subclass)
    Deprecated. 
    Returns a string that displays and identifies this object's properties.

    Methods declared in class java.lang.Object

    clone,finalize,getClass,notify,notifyAll,wait,wait,wait

  • Constructor Details

    • AWTKeyStroke

      protected AWTKeyStroke()
      Constructs anAWTKeyStroke with default values. The default values used are:
      AWTKeyStroke default values
      PropertyDefault Value
      Key CharKeyEvent.CHAR_UNDEFINED
      Key CodeKeyEvent.VK_UNDEFINED
      Modifiersnone
      On key release?false
      AWTKeyStrokes should not be constructed by client code. Use a variant ofgetAWTKeyStroke instead.
      See Also:

    • AWTKeyStroke

      protected AWTKeyStroke(char keyChar, int keyCode, int modifiers, boolean onKeyRelease)
      Constructs anAWTKeyStroke with the specified values.AWTKeyStrokes should not be constructed by client code. Use a variant ofgetAWTKeyStroke instead.
      Parameters:
      keyChar - the character value for a keyboard key
      keyCode - the key code for thisAWTKeyStroke
      modifiers - a bitwise-ored combination of any modifiers
      onKeyRelease -true if thisAWTKeyStroke corresponds to a key release;false otherwise
      See Also:

  • Method Details

    • registerSubclass

      @Deprecatedprotected static void registerSubclass(Class<?> subclass)
      Deprecated.
      The method has no effect and is only left present to avoid introducing a binary incompatibility.
      Parameters:
      subclass - the new Class of which the factory methods should create instances

    • getAWTKeyStroke

      public static AWTKeyStroke getAWTKeyStroke(char keyChar)
      Returns a shared instance of anAWTKeyStroke that represents aKEY_TYPED event for the specified character.
      Parameters:
      keyChar - the character value for a keyboard key
      Returns:
      anAWTKeyStroke object for that key

    • getAWTKeyStroke

      public static AWTKeyStroke getAWTKeyStroke(Character keyChar, int modifiers)
      Returns a shared instance of anAWTKeyStroke that represents aKEY_TYPED event for the specified 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 togetAWTKeyStroke(int keyCode, int modifiers). The modifiers consist of any combination of following:
      • java.awt.event.InputEvent.SHIFT_DOWN_MASK
      • java.awt.event.InputEvent.CTRL_DOWN_MASK
      • java.awt.event.InputEvent.META_DOWN_MASK
      • java.awt.event.InputEvent.ALT_DOWN_MASK
      • java.awt.event.InputEvent.ALT_GRAPH_DOWN_MASK
      The old modifiers listed below also can be used, but they are mapped to _DOWN_ modifiers.
      • java.awt.event.InputEvent.SHIFT_MASK
      • java.awt.event.InputEvent.CTRL_MASK
      • java.awt.event.InputEvent.META_MASK
      • java.awt.event.InputEvent.ALT_MASK
      • java.awt.event.InputEvent.ALT_GRAPH_MASK
      also can be used, but they are mapped to _DOWN_ modifiers. 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:
      anAWTKeyStroke object for that key
      Throws:
      IllegalArgumentException - ifkeyChar isnull
      See Also:

    • getAWTKeyStroke

      public static AWTKeyStroke getAWTKeyStroke(int keyCode, int modifiers, boolean onKeyRelease)
      Returns a shared instance of anAWTKeyStroke, 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 injava.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
      Alternatively, the key code may be obtained by callingjava.awt.event.KeyEvent.getExtendedKeyCodeForChar. The modifiers consist of any combination of:
      • java.awt.event.InputEvent.SHIFT_DOWN_MASK
      • java.awt.event.InputEvent.CTRL_DOWN_MASK
      • java.awt.event.InputEvent.META_DOWN_MASK
      • java.awt.event.InputEvent.ALT_DOWN_MASK
      • java.awt.event.InputEvent.ALT_GRAPH_DOWN_MASK
      The old modifiers
      • java.awt.event.InputEvent.SHIFT_MASK
      • java.awt.event.InputEvent.CTRL_MASK
      • java.awt.event.InputEvent.META_MASK
      • java.awt.event.InputEvent.ALT_MASK
      • java.awt.event.InputEvent.ALT_GRAPH_MASK
      also can be used, but they are mapped to _DOWN_ modifiers. 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 theAWTKeyStroke should represent a key release;false otherwise
      Returns:
      an AWTKeyStroke object for that key
      See Also:

    • getAWTKeyStroke

      public static AWTKeyStroke getAWTKeyStroke(int keyCode, int modifiers)
      Returns a shared instance of anAWTKeyStroke, given a numeric key code and a set of modifiers. The returnedAWTKeyStroke will correspond to a key press.

      The "virtual key" constants defined injava.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_DOWN_MASK
      • java.awt.event.InputEvent.CTRL_DOWN_MASK
      • java.awt.event.InputEvent.META_DOWN_MASK
      • java.awt.event.InputEvent.ALT_DOWN_MASK
      • java.awt.event.InputEvent.ALT_GRAPH_DOWN_MASK
      The old modifiers
      • java.awt.event.InputEvent.SHIFT_MASK
      • java.awt.event.InputEvent.CTRL_MASK
      • java.awt.event.InputEvent.META_MASK
      • java.awt.event.InputEvent.ALT_MASK
      • java.awt.event.InputEvent.ALT_GRAPH_MASK
      also can be used, but they are mapped to _DOWN_ modifiers. 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:
      anAWTKeyStroke object for that key
      See Also:

    • getAWTKeyStrokeForEvent

      public static AWTKeyStroke getAWTKeyStrokeForEvent(KeyEvent anEvent)
      Returns anAWTKeyStroke which represents the stroke which generated a givenKeyEvent.

      This method obtains the keyChar from aKeyTyped event, and the keyCode from aKeyPressed orKeyReleased event. TheKeyEvent modifiers are obtained for all three types ofKeyEvent.

      Parameters:
      anEvent - theKeyEvent from which to obtain theAWTKeyStroke
      Returns:
      theAWTKeyStroke that precipitated the event
      Throws:
      NullPointerException - ifanEvent is null

    • getAWTKeyStroke

      public static AWTKeyStroke getAWTKeyStroke(String s)
      Parses a string and returns anAWTKeyStroke. 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" => getAWTKeyStroke(KeyEvent.VK_INSERT, 0);     "control DELETE" => getAWTKeyStroke(KeyEvent.VK_DELETE, InputEvent.CTRL_MASK);     "alt shift X" => getAWTKeyStroke(KeyEvent.VK_X, InputEvent.ALT_MASK | InputEvent.SHIFT_MASK);     "alt shift released X" => getAWTKeyStroke(KeyEvent.VK_X, InputEvent.ALT_MASK | InputEvent.SHIFT_MASK, true);     "typed a" => getAWTKeyStroke('a');
      Parameters:
      s - a String formatted as described above
      Returns:
      anAWTKeyStroke object for that String
      Throws:
      IllegalArgumentException - ifs isnull, or is formatted incorrectly

    • getKeyChar

      public final char getKeyChar()
      Returns the character for thisAWTKeyStroke.
      Returns:
      a char value
      See Also:

    • getKeyCode

      public final int getKeyCode()
      Returns the numeric key code for thisAWTKeyStroke.
      Returns:
      an int containing the key code value
      See Also:

    • getModifiers

      public final int getModifiers()
      Returns the modifier keys for thisAWTKeyStroke.
      Returns:
      an int containing the modifiers
      See Also:

    • isOnKeyRelease

      public final boolean isOnKeyRelease()
      Returns whether thisAWTKeyStroke represents a key release.
      Returns:
      true if thisAWTKeyStroke represents a key release;false otherwise
      See Also:

    • getKeyEventType

      public final int getKeyEventType()
      Returns the type ofKeyEvent which corresponds to thisAWTKeyStroke.
      Returns:
      KeyEvent.KEY_PRESSED,KeyEvent.KEY_TYPED, orKeyEvent.KEY_RELEASED
      See Also:

    • hashCode

      public int hashCode()
      Returns a numeric value for this object that is likely to be unique, making it a good choice as the index value in a hash table.
      Overrides:
      hashCode in class Object
      Returns:
      an int that represents this object
      See Also:

    • equals

      public final boolean equals(Object anObject)
      Returns true if this object is identical to the specified object.
      Overrides:
      equals in class Object
      Parameters:
      anObject - the Object to compare this object to
      Returns:
      true if the objects are identical
      See Also:

    • toString

      public String toString()
      Returns a string that displays and identifies this object's properties. TheString returned by this method can be passed as a parameter togetAWTKeyStroke(String) to produce a key stroke equal to this key stroke.
      Overrides:
      toString in class Object
      Returns:
      a String representation of this object
      See Also:

    • readResolve

      protected Object readResolve() throwsObjectStreamException
      Returns a cached instance ofAWTKeyStroke (or a subclass ofAWTKeyStroke) which is equal to this instance.
      Returns:
      a cached instance which is equal to this instance
      Throws:
      ObjectStreamException - if a serialization problem occurs