java.awt
Class AWTKeyStrokejava.lang.Object | +--java.awt.AWTKeyStroke
- All Implemented Interfaces:
- Serializable
- Direct Known Subclasses:
- KeyStroke
- public class AWTKeyStroke
- extends Object
- implements 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, 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
Constructor Summary
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
boolean equals(Object anObject)
Returns true if this object is identical to the specified object.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(Character keyChar, int modifiers)
Returns a shared instance of an AWTKeyStroke, given a 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(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.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 Object readResolve()
Returns a cached instance of AWTKeyStroke (or a subclass of AWTKeyStroke) which is equal to this instance.protected static void registerSubclass(Class subclass)
Registers a new class which the factory methods in AWTKeyStroke will use when generating new instances of AWTKeyStrokes.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:
AWTKeyStrokes should not be constructed by client code. Use a variant of getAWTKeyStroke instead.
Key Char KeyEvent.CHAR_UNDEFINED Key Code KeyEvent.VK_UNDEFINED Modifiers none On key release? false
- 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
registerSubclass
protected static void registerSubclass(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:
- IllegalArgumentException - if subclass is null, or if subclass does not have a no-arg constructor
- 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(Character keyChar, int modifiers)
- Returns a shared instance of an AWTKeyStroke, 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 getAWTKeyStroke(int keyCode, int modifiers). The modifiers consist of any combination of:
The old modifiers
- 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
- java.awt.event.InputEvent.BUTTON1_DOWN_MASK
- java.awt.event.InputEvent.BUTTON2_DOWN_MASK
- java.awt.event.InputEvent.BUTTON3_DOWN_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.
- 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
- Parameters:
- keyChar - the Character object for a keyboard character
- modifiers - a bitwise-ored combination of any modifiers
- Returns:
- an AWTKeyStroke object for that key
- 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:
The modifiers consist of any combination of:
- java.awt.event.KeyEvent.VK_ENTER
- java.awt.event.KeyEvent.VK_TAB
- java.awt.event.KeyEvent.VK_SPACE
The old modifiers
- 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
- java.awt.event.InputEvent.BUTTON1_DOWN_MASK
- java.awt.event.InputEvent.BUTTON2_DOWN_MASK
- java.awt.event.InputEvent.BUTTON3_DOWN_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.
- 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
- 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:
The modifiers consist of any combination of:
- java.awt.event.KeyEvent.VK_ENTER
- java.awt.event.KeyEvent.VK_TAB
- java.awt.event.KeyEvent.VK_SPACE
The old modifiers
- 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
- java.awt.event.InputEvent.BUTTON1_DOWN_MASK
- java.awt.event.InputEvent.BUTTON2_DOWN_MASK
- java.awt.event.InputEvent.BUTTON3_DOWN_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.
- 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
- 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 key char from a KeyTyped event, and the key code 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
getAWTKeyStroke
public static AWTKeyStroke getAWTKeyStroke(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 | button1 | button2 | button3 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
getKeyChar
public final char getKeyChar()
- Returns the character for this AWTKeyStroke.
- Returns:
- a char value
- See Also:
- getAWTKeyStroke(char)
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)
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 Object
- Returns:
- an int that represents this object
- See Also:
- Object.equals(java.lang.Object), Hashtable
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:
- Object.hashCode(), Hashtable
toString
public String toString()
- Returns a string that displays and identifies this object's properties.
- Overrides:
- toString in class Object
- Returns:
- a String representation of this object
readResolve
protected Object readResolve() throws 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
- ObjectStreamException