All Packages  Class Hierarchy  This Package  Previous  Next  Index

Class guinea.util.EventQueue

java.lang.Object
   |
   +----guinea.util.EventQueue

public abstract class EventQueue

extends Object

Variable Index

· dispatcher

The event dispatcher thread.

· eventQueue

The queue used to send and receive events.

· isShared

Is this queue shared to other queues.

· quitThreadMarker

Dispatcher thread quit thread marker.

· sharedQueue

The queue we are sharing.

· threadName

Name for the dispatcher thread.

Constructor Index

· EventQueue()

Construct a new event queue with no name.

· EventQueue(EventQueue)

Construct a new event queue by sharing the event queue and thread of another event queue.

· EventQueue(String)

Construct a new event queue with given name for the dispatcher thread.

Method Index

· addListener()

Called as the first thing in all sub-classes' add*Listener methods.

· hasListeners()

Is there any more event listeners.

· postEvent(EventObject)

Put an event to the event queue.

· postEvent(EventObject, EventQueue)

Put an event to the event queue.

· processEvent(EventObject)

Process the event and send it to all listeners.

· removeListener()

Called as the last thing in all sub-classes' remove*Listener methods.

· setShared()

Mark this queue as shared.

Variables

 protected Queue eventQueue

The queue used to send and receive events.

 protected Thread dispatcher

The event dispatcher thread.

 protected String threadName

Name for the dispatcher thread.

 protected static final Object quitThreadMarker

Dispatcher thread quit thread marker.

 protected final EventQueue sharedQueue

The queue we are sharing.

 protected boolean isShared

Constructors

 public EventQueue()

 public EventQueue(String name)

Construct a new event queue with given name for the dispatcher thread.

Parameters:

name - the name for the dispatcher thread.

 public EventQueue(EventQueue share)

Construct a new event queue by sharing the event queue and thread of another event queue.

Parameters:

share - the other event queue whose queue to share.

Methods

 public abstract boolean hasListeners()

Is there any more event listeners.

Returns:

true if there are listeners registered.

 protected synchronized void setShared()

Mark this queue as shared. When a event queue is shared, several event queues use the same queue object and thread to dispatch the events. When a queue has been marked shared, it will not terminate the thread when all listeners have been removed. (it doesn't know whether the sharing queues still have listeners, knows only about the initial queue which is shared.

 protected void postEvent(EventObject e)

Put an event to the event queue. The dispatcher thread will receive the event from the queue and sends it to registered listeners. By default this will call postEvent(e, this).

Parameters:

e - an event to be sent.

 protected void postEvent(EventObject e,
                          EventQueue eq)

Put an event to the event queue. The dispatcher thread will receive the event from the queue and sends it to registered listeners.

Parameters:

e - an event to be sent.

eq - the event queue that originated this event.

 protected synchronized void addListener()

Called as the first thing in all sub-classes' add*Listener methods. When this is called the first time the event queue and the dispatcher thread are created.

 protected synchronized void removeListener()

Called as the last thing in all sub-classes' remove*Listener methods. When the last listener is removed, the dispatcher thread will be terminated and the internal event queue is removed if the queue isn't shared with other event queues.

 protected void processEvent(EventObject event)

Process the event and send it to all listeners. This is called by the dispatcher thread. Subclasses should extend this method to recognize its event types and process them appropiately. If an unknown event type is received, subclasses should pass it to super-class via super.processEvent(event) call.

Parameters:

event - the event to be sent to listeners.

All Packages  Class Hierarchy  This Package  Previous  Next  Index