- java.lang.Object
- 
- java.util.EventObject
- 
- java.awt.AWTEvent
- 
- java.awt.event.ActionEvent
 
 
 
- 
- All Implemented Interfaces:
- Serializable
 
 public class ActionEvent extends AWTEvent A semantic event which indicates that a component-defined action occurred. This high-level event is generated by a component (such as aButton) when the component-specific action occurs (such as being pressed). The event is passed to everyActionListenerobject that registered to receive such events using the component'saddActionListenermethod.Note: To invoke an ActionEventon aButtonusing the keyboard, use the Space bar.The object that implements the ActionListenerinterface gets thisActionEventwhen the event occurs. The listener is therefore spared the details of processing individual mouse movements and mouse clicks, and can instead process a "meaningful" (semantic) event like "button pressed".An unspecified behavior will be caused if the idparameter of any particularActionEventinstance is not in the range fromACTION_FIRSTtoACTION_LAST.- Since:
- 1.1
- See Also:
- ActionListener, Tutorial: How to Write an Action Listener, Serialized Form
 
- 
- 
Field SummaryFields Modifier and Type Field Description static intACTION_FIRSTThe first number in the range of ids used for action events.static intACTION_LASTThe last number in the range of ids used for action events.static intACTION_PERFORMEDThis event id indicates that a meaningful action occurred.static intALT_MASKThe alt modifier.static intCTRL_MASKThe control modifier.static intMETA_MASKThe meta modifier.static intSHIFT_MASKThe shift modifier.- 
Fields declared in class java.awt.AWTEventACTION_EVENT_MASK, ADJUSTMENT_EVENT_MASK, COMPONENT_EVENT_MASK, consumed, CONTAINER_EVENT_MASK, FOCUS_EVENT_MASK, HIERARCHY_BOUNDS_EVENT_MASK, HIERARCHY_EVENT_MASK, id, INPUT_METHOD_EVENT_MASK, INVOCATION_EVENT_MASK, ITEM_EVENT_MASK, KEY_EVENT_MASK, MOUSE_EVENT_MASK, MOUSE_MOTION_EVENT_MASK, MOUSE_WHEEL_EVENT_MASK, PAINT_EVENT_MASK, RESERVED_ID_MAX, TEXT_EVENT_MASK, WINDOW_EVENT_MASK, WINDOW_FOCUS_EVENT_MASK, WINDOW_STATE_EVENT_MASK
 - 
Fields declared in class java.util.EventObjectsource
 
- 
 - 
Constructor SummaryConstructors Constructor Description ActionEvent(Object source, int id, String command)Constructs anActionEventobject.ActionEvent(Object source, int id, String command, int modifiers)Constructs anActionEventobject with modifier keys.ActionEvent(Object source, int id, String command, long when, int modifiers)Constructs anActionEventobject with the specified modifier keys and timestamp.
 - 
Method SummaryAll Methods Instance Methods Concrete Methods Modifier and Type Method Description StringgetActionCommand()Returns the command string associated with this action.intgetModifiers()Returns the modifier keys held down during this action event.longgetWhen()Returns the timestamp of when this event occurred.StringparamString()Returns a parameter string identifying this action event.- 
Methods declared in class java.util.EventObjectgetSource
 
- 
 
- 
- 
- 
Field Detail- 
SHIFT_MASKpublic static final int SHIFT_MASK The shift modifier. An indicator that the shift key was held down during the event.- See Also:
- Constant Field Values
 
 - 
CTRL_MASKpublic static final int CTRL_MASK The control modifier. An indicator that the control key was held down during the event.- See Also:
- Constant Field Values
 
 - 
META_MASKpublic static final int META_MASK The meta modifier. An indicator that the meta key was held down during the event.- See Also:
- Constant Field Values
 
 - 
ALT_MASKpublic static final int ALT_MASK The alt modifier. An indicator that the alt key was held down during the event.- See Also:
- Constant Field Values
 
 - 
ACTION_FIRSTpublic static final int ACTION_FIRST The first number in the range of ids used for action events.- See Also:
- Constant Field Values
 
 - 
ACTION_LASTpublic static final int ACTION_LAST The last number in the range of ids used for action events.- See Also:
- Constant Field Values
 
 - 
ACTION_PERFORMED@Native public static final int ACTION_PERFORMED This event id indicates that a meaningful action occurred.- See Also:
- Constant Field Values
 
 
- 
 - 
Constructor Detail- 
ActionEventpublic ActionEvent(Object source, int id, String command) Constructs anActionEventobject.This method throws an IllegalArgumentExceptionifsourceisnull. Anull commandstring is legal, but not recommended.- Parameters:
- source- The object that originated the event
- id- An integer that identifies the event. For information on allowable values, see the class description for- ActionEvent
- command- A string that may specify a command (possibly one of several) associated with the event
- Throws:
- IllegalArgumentException- if- sourceis null
- See Also:
- EventObject.getSource(),- AWTEvent.getID(),- getActionCommand()
 
 - 
ActionEventpublic ActionEvent(Object source, int id, String command, int modifiers) Constructs anActionEventobject with modifier keys.This method throws an IllegalArgumentExceptionifsourceisnull. Anull commandstring is legal, but not recommended.- Parameters:
- source- The object that originated the event
- id- An integer that identifies the event. For information on allowable values, see the class description for- ActionEvent
- command- A string that may specify a command (possibly one of several) associated with the event
- modifiers- The modifier keys down during event (shift, ctrl, alt, meta). Passing negative parameter is not recommended. Zero value means that no modifiers were passed
- Throws:
- IllegalArgumentException- if- sourceis null
- See Also:
- EventObject.getSource(),- AWTEvent.getID(),- getActionCommand(),- getModifiers()
 
 - 
ActionEventpublic ActionEvent(Object source, int id, String command, long when, int modifiers) Constructs anActionEventobject with the specified modifier keys and timestamp.This method throws an IllegalArgumentExceptionifsourceisnull. Anull commandstring is legal, but not recommended.- Parameters:
- source- The object that originated the event
- id- An integer that identifies the event. For information on allowable values, see the class description for- ActionEvent
- command- A string that may specify a command (possibly one of several) associated with the event
- modifiers- The modifier keys down during event (shift, ctrl, alt, meta). Passing negative parameter is not recommended. Zero value means that no modifiers were passed
- when- A long that gives the time the event occurred. Passing negative or zero value is not recommended
- Throws:
- IllegalArgumentException- if- sourceis null
- Since:
- 1.4
- See Also:
- EventObject.getSource(),- AWTEvent.getID(),- getActionCommand(),- getModifiers(),- getWhen()
 
 
- 
 - 
Method Detail- 
getActionCommandpublic String getActionCommand() Returns the command string associated with this action. This string allows a "modal" component to specify one of several commands, depending on its state. For example, a single button might toggle between "show details" and "hide details". The source object and the event would be the same in each case, but the command string would identify the intended action.Note that if a nullcommand string was passed to the constructor for thisActionEvent, this this method returnsnull.- Returns:
- the string identifying the command for this event
 
 - 
getWhenpublic long getWhen() Returns the timestamp of when this event occurred. Because an ActionEvent is a high-level, semantic event, the timestamp is typically the same as an underlying InputEvent.- Returns:
- this event's timestamp
- Since:
- 1.4
 
 - 
getModifierspublic int getModifiers() Returns the modifier keys held down during this action event.- Returns:
- the bitwise-or of the modifier constants
 
 - 
paramStringpublic String paramString() Returns a parameter string identifying this action event. This method is useful for event-logging and for debugging.- Overrides:
- paramStringin class- AWTEvent
- Returns:
- a string identifying the event and its associated command
 
 
- 
 
-