SwingEventService.java

/**
 * Copyright 2005 Bushe Enterprises, Inc., Hopkinton, MA, USA, www.bushe.com
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.bushe.swing.event;

import javax.swing.*;
import java.util.Arrays;
import java.util.List;

/**
 * An {@link EventService} implementation for Swing.
 * <p/>
 * This class is Swing thread-safe.  All publish() calls NOT on the Swing EventDispatchThread thread are queued onto the
 * EDT.  If the calling thread is the EDT, then this is a simple pass-through (i.e the subscribers are notified on the
 * same stack frame, just like they would be had they added themselves via Swing addXXListener methods).
 *
 * @author Michael Bushe michael@bushe.com
 */
public class SwingEventService extends ThreadSafeEventService {

   /**
    * By default, the SwingEventService is constructed such that any listener that takes over 200 ms causes an
    * SubscriberTimingEvent to be published.  You will need to add a subscriber to this event.  Note that if you use
    * event to launch a modal dialog, the timings will be as long as the dialog is up - this is the way Swing works.
    */
   public SwingEventService() {
      super((long) 200, false, null, null, null);
   }

   public SwingEventService(Long timeThresholdForEventTimingEventPublication) {
      super(timeThresholdForEventTimingEventPublication, false, null, null, null);
   }

   /**
    * Create a SwingEventService is such that any listener that takes over timeThresholdForEventTimingEventPublication
    * milliseconds causes an EventSubscriberTimingEvent to be published.  You can add a subscriber to this event or set
    * subscribeTimingEventsInternally to true to cause the default logging to occur through the protected {@link
    * #subscribeTiming(SubscriberTimingEvent)} call.
    * <p/>
    * Note that if you use event to launch a modal dialog, the timings will be as long as the dialog is up - this is the
    * way Swing works.
    *
    * @param timeThresholdForEventTimingEventPublication the longest time a subscriber should spend handling an event,
    * The service will publish an SubscriberTimingEvent after listener processing if the time was exceeded.  If null, no
    * SubscriberTimingEvent will be issued.
    * @param subscribeTimingEventsInternally add a subscriber to the EventSubscriberTimingEvent internally and call the
    * protected {@link #subscribeTiming(SubscriberTimingEvent)} method when they occur.  This logs a warning to the
    * {@link Logger} logger by default.
    *
    * @throws IllegalArgumentException if timeThresholdForEventTimingEventPublication is null and
    * subscribeTimingEventsInternally is true.
    */
   public SwingEventService(Long timeThresholdForEventTimingEventPublication, boolean subscribeTimingEventsInternally) {
      super(timeThresholdForEventTimingEventPublication, subscribeTimingEventsInternally, null, null, null);
   }

   /**
    * Same as ThreadSafeEventService.publish(), except if the call is coming from a thread that is not the Swing Event
    * Dispatch Thread, the request is put on the EDT through a a call to SwingUtilities.invokeLater(). Otherwise this
    * DOES NOT post a new event on the EDT.  The subscribers are called on the same EDT event, just like addXXXListeners
    * would be.
    */
   protected void publish(final Object event, final String topic, final Object eventObj,
           final List subscribers, final List vetoSubscribers, final StackTraceElement[] callingStack) {
      if (SwingUtilities.isEventDispatchThread()) {
         super.publish(event, topic, eventObj, subscribers, vetoSubscribers, callingStack);
      } else {
         //Make call to this method - stick on the EDT if not on the EDT
         //Check the params first so that this thread can get the exception thrown
         SwingUtilities.invokeLater(new Runnable() {
            public void run() {
               if (LOG.isLoggable(Logger.Level.DEBUG)) {
                  LOG.debug("publish(" + event + "," + topic + "," + eventObj
                          + "), called from non-EDT Thread:" + Arrays.toString(callingStack));
               }
               SwingEventService.super.publish(event, topic, eventObj, subscribers, vetoSubscribers, callingStack);
            }
         });
      }
   }
}