Java Platform 1.2

java.awt.event
Class InvocationEvent

java.lang.Object
  |
  +--java.util.EventObject
        |
        +--java.awt.AWTEvent
              |
              +--java.awt.event.InvocationEvent

public class InvocationEvent
extends AWTEvent
implements ActiveEvent

An event which executes the run() method on a Runnable when dispatched by the AWT event dispatcher thread. This class can be used as a reference implementation of ActiveEvent rather than declaring a new class and defining dispatch().

Instances of this class are placed on the EventQueue by calls to invokeLater and invokeAndWait. Client code can use this fact to write replacement functions for invokeLater and invokeAndWait without writing special-case code in any EventQueueListener objects.

See Also:
ActiveEvent, EventQueue.invokeLater(java.lang.Runnable), EventQueue.invokeAndWait(java.lang.Runnable), EventQueueListener, Serialized Form

Field Summary
protected  boolean catchExceptions
          Set to true if dispatch() catches Exception and stores it in the exception instance variable.
static int INVOCATION_DEFAULT
          The default id for all InvocationEvents.
static int INVOCATION_FIRST
          Marks the first integer id for the range of invoke event ids.
static int INVOCATION_LAST
          Marks the last integer id for the range of invoke event ids.
protected  Object notifier
          The (potentially null) Object whose notifyAll() method will be called immediately after the Runnable.run() method returns.
protected  Runnable runnable
          The Runnable whose run() method will be called.
 
Fields inherited from class java.awt.AWTEvent
ACTION_EVENT_MASK, ADJUSTMENT_EVENT_MASK, COMPONENT_EVENT_MASK, consumed, CONTAINER_EVENT_MASK, FOCUS_EVENT_MASK, id, INPUT_METHOD_EVENT_MASK, ITEM_EVENT_MASK, KEY_EVENT_MASK, MOUSE_EVENT_MASK, MOUSE_MOTION_EVENT_MASK, RESERVED_ID_MAX, TEXT_EVENT_MASK, WINDOW_EVENT_MASK
 
Fields inherited from class java.util.EventObject
source
 
Constructor Summary
protected InvocationEvent(Object source, int id, Runnable runnable, Object notifier, boolean catchExceptions)
          Constructs an InvocationEvent with the specified source and ID which will execute the runnable's run() method when dispatched.
  InvocationEvent(Object source, Runnable runnable)
          Constructs an InvocationEvent with the specified source which will execute the runnable's run() method when dispatched.
  InvocationEvent(Object source, Runnable runnable, Object notifier, boolean catchExceptions)
          Constructs an InvocationEvent with the specified source which will execute the runnable's run() method when dispatched.
 
Method Summary
 void dispatch()
          Executes the Runnable's run() method and notifies the notifier (if any) when run() returns.
 Exception getException()
          Returns any Exception caught while executing the Runnable's run() method.
 String paramString()
          Returns a parameter string identifying this event.
 
Methods inherited from class java.awt.AWTEvent
consume, finalize, getID, isConsumed, toString
 
Methods inherited from class java.util.EventObject
getSource
 
Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Field Detail

INVOCATION_FIRST

public static final int INVOCATION_FIRST
Marks the first integer id for the range of invoke event ids.

INVOCATION_DEFAULT

public static final int INVOCATION_DEFAULT
The default id for all InvocationEvents.

INVOCATION_LAST

public static final int INVOCATION_LAST
Marks the last integer id for the range of invoke event ids.

runnable

protected Runnable runnable
The Runnable whose run() method will be called.

notifier

protected Object notifier
The (potentially null) Object whose notifyAll() method will be called immediately after the Runnable.run() method returns.

catchExceptions

protected boolean catchExceptions
Set to true if dispatch() catches Exception and stores it in the exception instance variable. If false, Exceptions are propagated up to the EventDispatchThread's dispatch loop.
Constructor Detail

InvocationEvent

public InvocationEvent(Object source,
                       Runnable runnable)
Constructs an InvocationEvent with the specified source which will execute the runnable's run() method when dispatched.
Parameters:
source - the Object that originated the event
runnable - the Runnable whose run() method will be executed

InvocationEvent

public InvocationEvent(Object source,
                       Runnable runnable,
                       Object notifier,
                       boolean catchExceptions)
Constructs an InvocationEvent with the specified source which will execute the runnable's run() method when dispatched. If notifier is non-null, notifyAll() will be called on it immediately after run() returns.
Parameters:
source - the Object that originated the event
runnable - the Runnable whose run() method will be executed
notifier - the Object whose notifyAll() method will be called after Runnable.run() has returned
catchExceptions - specifies whether dispatch() should catch Exception when executing the Runnable's run() method, or should instead propagate those Exceptions to the EventDispatchThread's dispatch loop

InvocationEvent

protected InvocationEvent(Object source,
                          int id,
                          Runnable runnable,
                          Object notifier,
                          boolean catchExceptions)
Constructs an InvocationEvent with the specified source and ID which will execute the runnable's run() method when dispatched. If notifier is non-null, notifyAll() will be called on it immediately after run() returns.
Parameters:
source - the Object that originated the event
id - the ID for the Event
runnable - the Runnable whose run() method will be executed
notifier - the Object whose notifyAll() method will be called after Runnable.run() has returned
catchExceptions - specifies whether dispatch() should catch Exception when executing the Runnable's run() method, or should instead propagate those Exceptions to the EventDispatchThread's dispatch loop
Method Detail

dispatch

public void dispatch()
Executes the Runnable's run() method and notifies the notifier (if any) when run() returns.
Specified by:
dispatch in interface ActiveEvent

getException

public Exception getException()
Returns any Exception caught while executing the Runnable's run() method.
Returns:
A reference to the Exception if one was thrown; null if no Exception was thrown or if this InvocationEvent does not catch exceptions

paramString

public String paramString()
Returns a parameter string identifying this event. This method is useful for event-logging and for debugging.
Returns:
A string identifying the event and its attributes
Overrides:
paramString in class AWTEvent

Java Platform 1.2

Submit a bug or feature Version 1.2 of Java Platform API Specification
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