Class AWTKeyStroke
- java.lang.Object
-
- java.awt.AWTKeyStroke
-
- All Implemented Interfaces:
- Serializable
- Direct Known Subclasses:
- KeyStroke
public class AWTKeyStroke extends Object implements Serializable
AnAWTKeyStroke
represents a key action on the keyboard, or equivalent input device.AWTKeyStroke
s can correspond to only a press or release of a particular key, just asKEY_PRESSED
andKEY_RELEASED
KeyEvent
s do; alternately, they can correspond to typing a specific Java character, just asKEY_TYPED
KeyEvent
s do. In all cases,AWTKeyStroke
s 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:
-
getAWTKeyStroke(char)
, Serialized Form
-
-
Constructor Summary
Constructors Modifier Constructor and Description protected
AWTKeyStroke()
Constructs anAWTKeyStroke
with default values.protected
AWTKeyStroke(char keyChar, int keyCode, int modifiers, boolean onKeyRelease)
Constructs anAWTKeyStroke
with the specified values.
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method and Description 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 anAWTKeyStroke
that represents aKEY_TYPED
event for the specified character.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.static AWTKeyStroke
getAWTKeyStroke(int keyCode, int modifiers)
Returns a shared instance of anAWTKeyStroke
, given a numeric key code and a set of modifiers.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.static AWTKeyStroke
getAWTKeyStroke(String s)
Parses a string and returns anAWTKeyStroke
.static AWTKeyStroke
getAWTKeyStrokeForEvent(KeyEvent anEvent)
Returns anAWTKeyStroke
which represents the stroke which generated a givenKeyEvent
.char
getKeyChar()
Returns the character for thisAWTKeyStroke
.int
getKeyCode()
Returns the numeric key code for thisAWTKeyStroke
.int
getKeyEventType()
Returns the type ofKeyEvent
which corresponds to thisAWTKeyStroke
.int
getModifiers()
Returns the modifier keys for thisAWTKeyStroke
.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 thisAWTKeyStroke
represents a key release.protected Object
readResolve()
Returns a cached instance ofAWTKeyStroke
(or a subclass ofAWTKeyStroke
) which is equal to this instance.protected static void
registerSubclass(Class<?> subclass)
Registers a new class which the factory methods inAWTKeyStroke
will use when generating new instances ofAWTKeyStroke
s.String
toString()
Returns a string that displays and identifies this object's properties.
-
-
-
Constructor Detail
AWTKeyStroke
protected AWTKeyStroke()
Constructs anAWTKeyStroke
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
AWTKeyStroke
s should not be constructed by client code. Use a variant ofgetAWTKeyStroke
instead.- See Also:
-
getAWTKeyStroke(char)
AWTKeyStroke
protected AWTKeyStroke(char keyChar, int keyCode, int modifiers, boolean onKeyRelease)
Constructs anAWTKeyStroke
with the specified values.AWTKeyStroke
s 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:
-
getAWTKeyStroke(char)
-
Method Detail
registerSubclass
protected static void registerSubclass(Class<?> subclass)
Registers a new class which the factory methods inAWTKeyStroke
will use when generating new instances ofAWTKeyStroke
s. After invoking this method, the factory methods will return instances of the specified Class. The specified Class must be eitherAWTKeyStroke
or derived fromAWTKeyStroke
, and it must have a no-arg constructor. The constructor can be of any accessibility, includingprivate
. This operation flushes the currentAWTKeyStroke
cache.- Parameters:
-
subclass
- the new Class of which the factory methods should create instances - Throws:
-
IllegalArgumentException
- if subclass isnull
, or if subclass does not have a no-arg constructor -
ClassCastException
- if subclass is notAWTKeyStroke
, or a class derived fromAWTKeyStroke
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:
-
an
AWTKeyStroke
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
- 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 - Throws:
-
IllegalArgumentException
- ifkeyChar
isnull
- See Also:
-
InputEvent
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 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
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
- 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 theAWTKeyStroke
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 anAWTKeyStroke
, given a numeric key code and a set of modifiers. The returnedAWTKeyStroke
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
- 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.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 anAWTKeyStroke
which represents the stroke which generated a givenKeyEvent
.This method obtains the keyChar from a
KeyTyped
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:
-
the
AWTKeyStroke
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:
-
an
AWTKeyStroke
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:
-
getAWTKeyStroke(char)
,KeyEvent.getKeyChar()
getKeyCode
public final int getKeyCode()
Returns the numeric key code for thisAWTKeyStroke
.- 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 thisAWTKeyStroke
.- Returns:
- an int containing the modifiers
- See Also:
-
getAWTKeyStroke(int,int)
isOnKeyRelease
public final boolean isOnKeyRelease()
Returns whether thisAWTKeyStroke
represents a key release.- Returns:
-
true
if thisAWTKeyStroke
represents a key release;false
otherwise - See Also:
-
getAWTKeyStroke(int,int,boolean)
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:
-
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 classObject
- Returns:
- an int that represents this object
- See Also:
-
Object.equals(java.lang.Object)
,System.identityHashCode(java.lang.Object)
equals
public final boolean equals(Object anObject)
Returns true if this object is identical to the specified object.- Overrides:
-
equals
in classObject
- Parameters:
-
anObject
- the Object to compare this object to - Returns:
- true if the objects are identical
- See Also:
-
Object.hashCode()
,HashMap
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 classObject
- Returns:
- a String representation of this object
- See Also:
-
getAWTKeyStroke(String)
readResolve
protected Object readResolve() throws ObjectStreamException
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
-
Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2022, Oracle and/or its affiliates. All rights reserved. Use is subject to license terms. Also see the documentation redistribution policy.