java.awt.event
Class InvocationEvent

java.lang.Object
  java.util.EventObject
      java.awt.AWTEvent
          java.awt.event.InvocationEvent

All Implemented Interfaces:

ActiveEvent, Serializable

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 AWTEventListener objects.

Since:

1.2

Author:

Fred Ecks, David Mendenhall

See Also:

ActiveEvent, EventQueue.invokeLater(java.lang.Runnable), EventQueue.invokeAndWait(java.lang.Runnable), AWTEventListener, Serialized Form

Field Summary

protected boolean	catchExceptions Set to true if dispatch() catches Exception and stores it in the exception instance variable.
private Exception	exception The (potentially null) Exception thrown during execution of the Runnable.run() method.
static int	INVOCATION_DEFAULT The default id for all InvocationEvents.
static int	INVOCATION_FIRST Marks the first integer id for the range of invocation event ids.
static int	INVOCATION_LAST Marks the last integer id for the range of invocation 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.
private static long	serialVersionUID
private long	when The timestamp of when this event occurred.

Fields inherited from class java.awt.AWTEvent

ACTION_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 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.
long	getWhen() Returns the timestamp of when this event occurred.
String	paramString() Returns a parameter string identifying this event.

Methods inherited from class java.awt.AWTEvent

consume, getID, isConsumed, setSource, toString

Methods inherited from class java.util.EventObject

getSource

Methods inherited from class java.lang.Object

clone, equals, finalize, 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 invocation event ids.

See Also:

Constant Field Values

INVOCATION_DEFAULT

public static final int INVOCATION_DEFAULT

The default id for all InvocationEvents.

See Also:

Constant Field Values

INVOCATION_LAST

public static final int INVOCATION_LAST

Marks the last integer id for the range of invocation event ids.

See Also:

Constant Field Values

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.

exception

private Exception exception

The (potentially null) Exception thrown during execution of the Runnable.run() method. This variable will also be null if a particular instance does not catch exceptions.

when

private long when

The timestamp of when this event occurred.

See Also:

getWhen()

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

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.

Note that passing in an invalid id results in unspecified behavior.

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

getWhen

public long getWhen()

Returns the timestamp of when this event occurred.

Returns:

this event's timestamp

Since:

1.4

paramString

public String paramString()

Returns a parameter string identifying this event. This method is useful for event-logging and for debugging.

Overrides:

paramString in class AWTEvent

Returns:

A string identifying the event and its attributes