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java.awt.event
public class: ActionEvent [javadoc | source]
java.lang.Object
   java.util.EventObject
      java.awt.AWTEvent
         java.awt.event.ActionEvent

All Implemented Interfaces:
    Serializable

Direct Known Subclasses:
    StopThreadEvent

A semantic event which indicates that a component-defined action occurred. This high-level event is generated by a component (such as a Button) when the component-specific action occurs (such as being pressed). The event is passed to every ActionListener object that registered to receive such events using the component's addActionListener method.

Note: To invoke an ActionEvent on a Button using the keyboard, use the Space bar.

The object that implements the ActionListener interface gets this ActionEvent when 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 {@code id} parameter of any particular {@code ActionEvent} instance is not in the range from {@code ACTION_FIRST} to {@code ACTION_LAST}.

Field Summary
public static final  int SHIFT_MASK    The shift modifier. An indicator that the shift key was held down during the event. 
public static final  int CTRL_MASK    The control modifier. An indicator that the control key was held down during the event. 
public static final  int META_MASK    The meta modifier. An indicator that the meta key was held down during the event. 
public static final  int ALT_MASK    The alt modifier. An indicator that the alt key was held down during the event. 
public static final  int ACTION_FIRST    The first number in the range of ids used for action events. 
public static final  int ACTION_LAST    The last number in the range of ids used for action events. 
public static final  int ACTION_PERFORMED    This event id indicates that a meaningful action occured. 
 String actionCommand    The nonlocalized string that gives more details of what actually caused the event. This information is very specific to the component that fired it. 
 long when    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. 
 int modifiers    This represents the key modifier that was selected, and is used to determine the state of the selected key. If no modifier has been selected it will default to zero. 
Fields inherited from java.awt.AWTEvent:
id,  consumed,  focusManagerIsDispatching,  isPosted,  COMPONENT_EVENT_MASK,  CONTAINER_EVENT_MASK,  FOCUS_EVENT_MASK,  KEY_EVENT_MASK,  MOUSE_EVENT_MASK,  MOUSE_MOTION_EVENT_MASK,  WINDOW_EVENT_MASK,  ACTION_EVENT_MASK,  ADJUSTMENT_EVENT_MASK,  ITEM_EVENT_MASK,  TEXT_EVENT_MASK,  INPUT_METHOD_EVENT_MASK,  INPUT_METHODS_ENABLED_MASK,  PAINT_EVENT_MASK,  INVOCATION_EVENT_MASK,  HIERARCHY_EVENT_MASK,  HIERARCHY_BOUNDS_EVENT_MASK,  MOUSE_WHEEL_EVENT_MASK,  WINDOW_STATE_EVENT_MASK,  WINDOW_FOCUS_EVENT_MASK,  RESERVED_ID_MAX
Fields inherited from java.util.EventObject:
source
Constructor:
 public ActionEvent(Object source,
    int id,
    String command) 
    Constructs an ActionEvent object.

    This method throws an IllegalArgumentException if source is null. A null command string 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 source is null
    Also see:
    getSource()
    getID()
    getActionCommand()
 public ActionEvent(Object source,
    int id,
    String command,
    int modifiers) 
    Constructs an ActionEvent object with modifier keys.

    This method throws an IllegalArgumentException if source is null. A null command string 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 source is null
    Also see:
    getSource()
    getID()
    getActionCommand()
    getModifiers()
 public ActionEvent(Object source,
    int id,
    String command,
    long when,
    int modifiers) 
    Constructs an ActionEvent object with the specified modifier keys and timestamp.

    This method throws an IllegalArgumentException if source is null. A null command string 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 source is null
    Also see:
    getSource()
    getID()
    getActionCommand()
    getModifiers()
    getWhen()
    since: 1.4 -
Method from java.awt.event.ActionEvent Summary:
getActionCommand,   getModifiers,   getWhen,   paramString
Methods from java.awt.AWTEvent:
consume,   convertToOld,   copyPrivateDataInto,   dispatched,   getAccessControlContext,   getID,   isConsumed,   paramString,   setSource,   toString
Methods from java.util.EventObject:
getSource,   toString
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from java.awt.event.ActionEvent Detail:
 public 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 null command string was passed to the constructor for this ActionEvent, this this method returns null.

 public int getModifiers() 
    Returns the modifier keys held down during this action event.
 public 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.
 public String paramString() 
    Returns a parameter string identifying this action event. This method is useful for event-logging and for debugging.