AWTKeyStroke (Sample Document)

java.lang.Object
- java.awt.AWTKeyStroke

All Implemented Interfaces:

java.io.Serializable

public class AWTKeyStroke extends java.lang.Object implements java.io.Serializable

An AWTKeyStroke 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 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, 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 an AWTKeyStroke on its own, but should instead use a variant of getAWTKeyStroke. Client use of these factory methods allows the AWTKeyStroke implementation to cache and share instances efficiently.

Since:

1.4

See Also:
getAWTKeyStroke(char), Serialized Form

Static Method Summary

Static Methods
Modifier and Type	Static Method and Description
`static AWTKeyStroke`	`getAWTKeyStroke(char keyChar)` Returns a shared instance of an `AWTKeyStroke` that represents a `KEY_TYPED` event for the specified character.
`static AWTKeyStroke`	`getAWTKeyStroke(java.lang.Character keyChar, int modifiers)` Returns a shared instance of an `AWTKeyStroke` that represents a `KEY_TYPED` event for the specified Character object and a set of modifiers.
`static AWTKeyStroke`	`getAWTKeyStroke(int keyCode, int modifiers)` Returns a shared instance of an `AWTKeyStroke`, given a numeric key code and a set of modifiers.
`static AWTKeyStroke`	`getAWTKeyStroke(int keyCode, int modifiers, boolean onKeyRelease)` Returns a shared instance of an `AWTKeyStroke`, given a numeric key code and a set of modifiers, specifying whether the key is activated when it is pressed or released.
`static AWTKeyStroke`	`getAWTKeyStroke(java.lang.String s)` Parses a string and returns an `AWTKeyStroke`.
`static AWTKeyStroke`	`getAWTKeyStrokeForEvent(KeyEvent anEvent)` Returns an `AWTKeyStroke` which represents the stroke which generated a given `KeyEvent`.
`protected static void`	`registerSubclass(java.lang.Class<?> subclass)` Registers a new class which the factory methods in `AWTKeyStroke` will use when generating new instances of `AWTKeyStroke`s.

Constructor Summary

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

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`equals(java.lang.Object anObject)` Returns true if this object is identical to the specified object.
`char`	`getKeyChar()` Returns the character for this `AWTKeyStroke`.
`int`	`getKeyCode()` Returns the numeric key code for this `AWTKeyStroke`.
`int`	`getKeyEventType()` Returns the type of `KeyEvent` which corresponds to this `AWTKeyStroke`.
`int`	`getModifiers()` Returns the modifier keys for this `AWTKeyStroke`.
`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.
`boolean`	`isOnKeyRelease()` Returns whether this `AWTKeyStroke` represents a key release.
`protected java.lang.Object`	`readResolve()` Returns a cached instance of `AWTKeyStroke` (or a subclass of `AWTKeyStroke`) which is equal to this instance.
`java.lang.String`	`toString()` Returns a string that displays and identifies this object's properties.

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

- Constructor Detail
  - AWTKeyStroke
    
    protected AWTKeyStroke()
    
    Constructs an AWTKeyStroke with default values. The default values used are:
    
    Property Default Value
    
    Key Char KeyEvent.CHAR_UNDEFINED
    
    Key Code KeyEvent.VK_UNDEFINED
    
    Modifiers none
    
    On key release? false
    
    AWTKeyStrokes should not be constructed by client code. Use a variant of getAWTKeyStroke instead.
    
    See Also:
    getAWTKeyStroke(char)
  - AWTKeyStroke
    
    protected AWTKeyStroke(char keyChar, int keyCode, int modifiers, boolean onKeyRelease)
    
    Constructs an AWTKeyStroke with the specified values. AWTKeyStrokes should not be constructed by client code. Use a variant of getAWTKeyStroke instead.
    
    Parameters:
    keyChar - the character value for a keyboard key
    keyCode - the key code for this AWTKeyStroke
    modifiers - a bitwise-ored combination of any modifiers
    onKeyRelease - true if this AWTKeyStroke corresponds to a key release; false otherwise
    See Also:
    getAWTKeyStroke(char)
- Method Detail
  - getKeyChar
    
    public final char getKeyChar()
    
    Returns the character for this AWTKeyStroke.
    
    Returns:
    a char value
    See Also:
    getAWTKeyStroke(char), KeyEvent.getKeyChar()
  - getKeyCode
    
    public final int getKeyCode()
    
    Returns the numeric key code for this AWTKeyStroke.
    
    Returns:
    an int containing the key code value
    See Also:
    getAWTKeyStroke(int,int), KeyEvent.getKeyCode()
  - getModifiers
    
    public final int getModifiers()
    
    Returns the modifier keys for this AWTKeyStroke.
    
    Returns:
    an int containing the modifiers
    See Also:
    getAWTKeyStroke(int,int)
  - isOnKeyRelease
    
    public final boolean isOnKeyRelease()
    
    Returns whether this AWTKeyStroke represents a key release.
    
    Returns:
    true if this AWTKeyStroke represents a key release; false otherwise
    See Also:
    getAWTKeyStroke(int,int,boolean)
  - getKeyEventType
    
    public final int getKeyEventType()
    
    Returns the type of KeyEvent which corresponds to this AWTKeyStroke.
    
    Returns:
    KeyEvent.KEY_PRESSED, KeyEvent.KEY_TYPED, or KeyEvent.KEY_RELEASED
    See Also:
    KeyEvent
  - 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 java.lang.Object
    
    Returns:
    an int that represents this object
    See Also:
    Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)
  - equals
    
    public final boolean equals(java.lang.Object anObject)
    
    Returns true if this object is identical to the specified object.
    
    Overrides:
    
    equals in class java.lang.Object
    
    Parameters:
    anObject - the Object to compare this object to
    
    Returns:
    true if the objects are identical
    See Also:
    Object.hashCode(), HashMap
  - toString
    
    public java.lang.String toString()
    
    Returns a string that displays and identifies this object's properties. The String returned by this method can be passed as a parameter to getAWTKeyStroke(String) to produce a key stroke equal to this key stroke.
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    a String representation of this object
    See Also:
    getAWTKeyStroke(String)
  - readResolve
    
    protected java.lang.Object readResolve() throws java.io.ObjectStreamException
    
    Returns a cached instance of AWTKeyStroke (or a subclass of AWTKeyStroke) which is equal to this instance.
    
    Returns:
    a cached instance which is equal to this instance
    
    Throws:
    
    java.io.ObjectStreamException
- Static Method Detail
  - registerSubclass
    
    protected static void registerSubclass(java.lang.Class<?> subclass)
    
    Registers a new class which the factory methods in AWTKeyStroke will use when generating new instances of AWTKeyStrokes. After invoking this method, the factory methods will return instances of the specified Class. The specified Class must be either AWTKeyStroke or derived from AWTKeyStroke, and it must have a no-arg constructor. The constructor can be of any accessibility, including private. This operation flushes the current AWTKeyStroke cache.
    
    Parameters:
    subclass - the new Class of which the factory methods should create instances
    
    Throws:
    
    java.lang.IllegalArgumentException - if subclass is null, or if subclass does not have a no-arg constructor
    
    java.lang.ClassCastException - if subclass is not AWTKeyStroke, or a class derived from AWTKeyStroke
  - getAWTKeyStroke
    
    public static AWTKeyStroke getAWTKeyStroke(char keyChar)
    
    Returns a shared instance of an AWTKeyStroke that represents a KEY_TYPED event for the specified character.
    
    Parameters:
    keyChar - the character value for a keyboard key
    
    Returns:
    an AWTKeyStroke object for that key
  - getAWTKeyStroke
    
    public static AWTKeyStroke getAWTKeyStroke(java.lang.Character keyChar, int modifiers)
    Returns a shared instance of an AWTKeyStroke that represents a KEY_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 to getAWTKeyStroke(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:
    an AWTKeyStroke object for that key
    
    Throws:
    
    java.lang.IllegalArgumentException - if keyChar is null
    See Also:
    InputEvent
  - getAWTKeyStroke
    
    public static AWTKeyStroke getAWTKeyStroke(int keyCode, int modifiers, boolean onKeyRelease)
    Returns a shared instance of an AWTKeyStroke, 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
    Alternatively, the key code may be obtained by calling java.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 the AWTKeyStroke should represent a key release; false otherwise
    
    Returns:
    an AWTKeyStroke object for that key
    See Also:
    KeyEvent, InputEvent
  - getAWTKeyStroke
    
    public static AWTKeyStroke getAWTKeyStroke(int keyCode, int modifiers)
    Returns a shared instance of an AWTKeyStroke, given a numeric key code and a set of modifiers. The returned AWTKeyStroke 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_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:
    an AWTKeyStroke object for that key
    See Also:
    KeyEvent, InputEvent
  - getAWTKeyStrokeForEvent
    
    public static AWTKeyStroke getAWTKeyStrokeForEvent(KeyEvent anEvent)
    
    Returns an AWTKeyStroke 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 AWTKeyStroke
    
    Returns:
    the AWTKeyStroke that precipitated the event
    
    Throws:
    
    java.lang.NullPointerException - if anEvent is null
  - getAWTKeyStroke
    
    public static AWTKeyStroke getAWTKeyStroke(java.lang.String s)
    Parses a string and returns an AWTKeyStroke. 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:
    an AWTKeyStroke object for that String
    
    Throws:
    
    java.lang.IllegalArgumentException - if s is null, or is formatted incorrectly

Property	Default Value
Key Char	`KeyEvent.CHAR_UNDEFINED`
Key Code	`KeyEvent.VK_UNDEFINED`
Modifiers	none
On key release?	`false`

Class AWTKeyStroke

Static Method Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

AWTKeyStroke

AWTKeyStroke

Method Detail

getKeyChar

getKeyCode

getModifiers

isOnKeyRelease

getKeyEventType

hashCode

equals

toString

readResolve

Static Method Detail

registerSubclass

getAWTKeyStroke

getAWTKeyStroke

getAWTKeyStroke

getAWTKeyStroke

getAWTKeyStrokeForEvent

getAWTKeyStroke