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Diffstat (limited to 'bundles/org.eclipse.osgi/supplement/src/org/eclipse/osgi/framework/eventmgr/ListenerQueue.java')
| -rw-r--r-- | bundles/org.eclipse.osgi/supplement/src/org/eclipse/osgi/framework/eventmgr/ListenerQueue.java | 152 |
1 files changed, 0 insertions, 152 deletions
diff --git a/bundles/org.eclipse.osgi/supplement/src/org/eclipse/osgi/framework/eventmgr/ListenerQueue.java b/bundles/org.eclipse.osgi/supplement/src/org/eclipse/osgi/framework/eventmgr/ListenerQueue.java deleted file mode 100644 index 0f63ecc18..000000000 --- a/bundles/org.eclipse.osgi/supplement/src/org/eclipse/osgi/framework/eventmgr/ListenerQueue.java +++ /dev/null @@ -1,152 +0,0 @@ -/******************************************************************************* - * Copyright (c) 2003, 2009 IBM Corporation and others. - * All rights reserved. This program and the accompanying materials - * are made available under the terms of the Eclipse Public License v1.0 - * which accompanies this distribution, and is available at - * http://www.eclipse.org/legal/epl-v10.html - * - * Contributors: - * IBM Corporation - initial API and implementation - *******************************************************************************/ - -package org.eclipse.osgi.framework.eventmgr; - -import java.util.*; -import org.eclipse.osgi.framework.eventmgr.EventManager.EventThread; - -/** - * The ListenerQueue is used to snapshot the list of listeners at the time the event - * is fired. The snapshot list is then used to dispatch - * events to those listeners. A ListenerQueue object is associated with a - * specific EventManager object. ListenerQueue objects constructed with the same - * EventManager object will get in-order delivery of events when - * using asynchronous delivery. No delivery order is guaranteed for synchronous - * delivery to avoid any potential deadly embraces. - * - * <p>ListenerQueue objects are created as necessary to build a list of listeners - * that should receive a specific event or events. Once the list is created, the event - * can then be synchronously or asynchronously delivered to the list of - * listeners. After the event has been dispatched for delivery, the - * ListenerQueue object should be discarded as it is likely the list of listeners is stale. - * A new ListenerQueue object should be created when it is time to deliver - * another event. The Sets used to build the list of listeners must not change after being - * added to the list. - * @since 3.1 - */ -public class ListenerQueue { - /** - * EventManager with which this queue is associated. - */ - protected final EventManager manager; - /** - * A list of listener lists. - */ - private final Map /*<Set<Map.Entry<Object,Object>>,EventDispatcher>*/queue; - - /** - * Once the listener queue has been used to dispatch an event, - * you cannot add modify the queue. - * Access to this field must be protected by a synchronized region. - */ - private boolean readOnly; - - /** - * ListenerQueue constructor. This method creates an empty snapshot list. - * - * @param manager The EventManager this queue is associated with. - * @throws IllegalArgumentException If manager is null. - */ - public ListenerQueue(EventManager manager) { - if (manager == null) { - throw new IllegalArgumentException(); - } - - this.manager = manager; - queue = new CopyOnWriteIdentityMap(); - readOnly = false; - } - - /** - * Add a listener list to the snapshot list. This method can be called multiple times, prior to - * calling one of the dispatchEvent methods, to build the set of listeners for the - * delivery of a specific event. The current list of listeners in the specified EventListeners - * object is added to the snapshot list. - * - * @param listeners An EventListeners object to add to the queue. The current listeners - * in the EventListeners object will be called when an event is dispatched. - * @param dispatcher An EventDispatcher object to use when dispatching an event - * to the listeners on the specified EventListeners. - * @throws IllegalStateException If called after one of the dispatch methods has been called. - * @deprecated As of 3.5. Replaced by {@link #queueListeners(Set, EventDispatcher)}. - */ - public void queueListeners(EventListeners listeners, EventDispatcher dispatcher) { - queueListeners(listeners.entrySet(), dispatcher); - } - - /** - * Add a set of listeners to the snapshot list. This method can be called multiple times, prior to - * calling one of the dispatchEvent methods, to build the list of listeners for the - * delivery of a specific event. The specified listeners - * are added to the snapshot list. - * - * @param listeners A Set of Map.Entries to add to the queue. This is typically the entrySet - * from a CopyOnWriteIdentityMap object. This set must not change after being added to this - * snapshot list. - * @param dispatcher An EventDispatcher object to use when dispatching an event - * to the specified listeners. - * @throws IllegalStateException If called after one of the dispatch methods has been called. - * @since 3.5 - */ - public synchronized void queueListeners(Set/*<Map.Entry<Object,Object>>*/listeners, EventDispatcher dispatcher) { - if (readOnly) { - throw new IllegalStateException(); - } - - if (listeners.size() != 0) { - queue.put(listeners, dispatcher); // enqueue the list and its dispatcher - } - } - - /** - * Asynchronously dispatch an event to the snapshot list. An event dispatch thread - * maintained by the associated EventManager is used to deliver the events. - * This method may return immediately to the caller. - * - * @param eventAction This value is passed to the EventDispatcher. - * @param eventObject This object is passed to the EventDispatcher. - */ - public void dispatchEventAsynchronous(int eventAction, Object eventObject) { - synchronized (this) { - readOnly = true; - } - EventThread eventThread = manager.getEventThread(); - synchronized (eventThread) { /* synchronize on the EventThread to ensure no interleaving of posting to the event thread */ - for (Iterator iter = queue.entrySet().iterator(); iter.hasNext();) { /* iterate over the list of listener lists */ - Map.Entry entry = (Map.Entry) iter.next(); - eventThread.postEvent((Set) entry.getKey(), (EventDispatcher) entry.getValue(), eventAction, eventObject); - } - } - } - - /** - * Synchronously dispatch an event to the snapshot list. The event may - * be dispatched on the current thread or an event dispatch thread - * maintained by the associated EventManager. - * This method will not return to the caller until the EventDispatcher - * has been called (and has returned) for each listener on the queue. - * - * @param eventAction This value is passed to the EventDispatcher. - * @param eventObject This object is passed to the EventDispatcher. - */ - public void dispatchEventSynchronous(int eventAction, Object eventObject) { - synchronized (this) { - readOnly = true; - } - // We can't guarantee any delivery order for synchronous events. - // Attempts to do so result in deadly embraces. - for (Iterator iter = queue.entrySet().iterator(); iter.hasNext();) { /* iterate over the list of listener lists */ - Map.Entry entry = (Map.Entry) iter.next(); - EventManager.dispatchEvent((Set) entry.getKey(), (EventDispatcher) entry.getValue(), eventAction, eventObject); - } - } -} |