Class AWTKeyStroke
- java.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. AWTKeyStroke
s can correspond to only a press or release of a particular key, just as KEY_PRESSED
and KEY_RELEASED KeyEvent
s do; alternately, they can correspond to typing a specific Java character, just as KEY_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 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
Modifier | Constructor | Description |
---|---|---|
protected | AWTKeyStroke() | Constructs an |
protected | AWTKeyStroke(char keyChar,
int keyCode,
int modifiers,
boolean onKeyRelease) | Constructs an |
Method Summary
Modifier and Type | Method | 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 an |
static AWTKeyStroke | getAWTKeyStroke(int keyCode,
int modifiers) | Returns a shared instance of an |
static AWTKeyStroke | getAWTKeyStroke(int keyCode,
int modifiers,
boolean onKeyRelease) | Returns a shared instance of an |
static AWTKeyStroke | getAWTKeyStroke(Character keyChar,
int modifiers) | Returns a shared instance of an |
static AWTKeyStroke | getAWTKeyStroke(String s) | Parses a string and returns an |
static AWTKeyStroke | getAWTKeyStrokeForEvent(KeyEvent anEvent) | Returns an |
char | getKeyChar() | Returns the character for this |
int | getKeyCode() | Returns the numeric key code for this |
int | getKeyEventType() | Returns the type of |
int | getModifiers() | Returns the modifier keys for this |
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 |
protected Object | readResolve() | Returns a cached instance of |
protected static void | registerSubclass(Class<?> subclass) | Deprecated. |
String | toString() | 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 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 |
AWTKeyStroke
s 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. AWTKeyStroke
s 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 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
@Deprecated protected static void registerSubclass(Class<?> subclass)
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 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
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
- 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 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
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 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
- 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 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
- 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 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:
-
IllegalArgumentException
- ifs
isnull
, or is formatted incorrectly
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 thisAWTKeyStroke
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
, 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. 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 classObject
- Returns:
- a String representation of this object
- See Also:
getAWTKeyStroke(String)
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
- Throws:
-
ObjectStreamException
- if a serialization problem occurs