| /* |
| * Copyright (c) 1998, 2008, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.awt.event; |
| |
| import java.awt.ActiveEvent; |
| import java.awt.AWTEvent; |
| |
| /** |
| * An event which executes the <code>run()</code> method on a <code>Runnable |
| * </code> when dispatched by the AWT event dispatcher thread. This class can |
| * be used as a reference implementation of <code>ActiveEvent</code> rather |
| * than declaring a new class and defining <code>dispatch()</code>.<p> |
| * |
| * Instances of this class are placed on the <code>EventQueue</code> by calls |
| * to <code>invokeLater</code> and <code>invokeAndWait</code>. Client code |
| * can use this fact to write replacement functions for <code>invokeLater |
| * </code> and <code>invokeAndWait</code> without writing special-case code |
| * in any <code>AWTEventListener</code> objects. |
| * <p> |
| * An unspecified behavior will be caused if the {@code id} parameter |
| * of any particular {@code InvocationEvent} instance is not |
| * in the range from {@code INVOCATION_FIRST} to {@code INVOCATION_LAST}. |
| * |
| * @author Fred Ecks |
| * @author David Mendenhall |
| * |
| * @see java.awt.ActiveEvent |
| * @see java.awt.EventQueue#invokeLater |
| * @see java.awt.EventQueue#invokeAndWait |
| * @see AWTEventListener |
| * |
| * @since 1.2 |
| */ |
| public class InvocationEvent extends AWTEvent implements ActiveEvent { |
| |
| /** |
| * Marks the first integer id for the range of invocation event ids. |
| */ |
| public static final int INVOCATION_FIRST = 1200; |
| |
| /** |
| * The default id for all InvocationEvents. |
| */ |
| public static final int INVOCATION_DEFAULT = INVOCATION_FIRST; |
| |
| /** |
| * Marks the last integer id for the range of invocation event ids. |
| */ |
| public static final int INVOCATION_LAST = INVOCATION_DEFAULT; |
| |
| /** |
| * The Runnable whose run() method will be called. |
| */ |
| protected Runnable runnable; |
| |
| /** |
| * The (potentially null) Object whose notifyAll() method will be called |
| * immediately after the Runnable.run() method has returned or thrown an exception. |
| * |
| * @see #isDispatched |
| */ |
| protected Object notifier; |
| |
| /** |
| * Indicates whether the <code>run()</code> method of the <code>runnable</code> |
| * was executed or not. |
| * |
| * @see #isDispatched |
| * @since 1.7 |
| */ |
| private volatile boolean dispatched = false; |
| |
| /** |
| * Set to true if dispatch() catches Throwable and stores it in the |
| * exception instance variable. If false, Throwables are propagated up |
| * to the EventDispatchThread's dispatch loop. |
| */ |
| protected boolean catchExceptions; |
| |
| /** |
| * 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. |
| */ |
| private Exception exception = null; |
| |
| /** |
| * The (potentially null) Throwable thrown during execution of the |
| * Runnable.run() method. This variable will also be null if a particular |
| * instance does not catch exceptions. |
| */ |
| private Throwable throwable = null; |
| |
| /** |
| * The timestamp of when this event occurred. |
| * |
| * @serial |
| * @see #getWhen |
| */ |
| private long when; |
| |
| /* |
| * JDK 1.1 serialVersionUID. |
| */ |
| private static final long serialVersionUID = 436056344909459450L; |
| |
| /** |
| * Constructs an <code>InvocationEvent</code> with the specified |
| * source which will execute the runnable's <code>run</code> |
| * method when dispatched. |
| * <p>This is a convenience constructor. An invocation of the form |
| * <tt>InvocationEvent(source, runnable)</tt> |
| * behaves in exactly the same way as the invocation of |
| * <tt>{@link #InvocationEvent(Object, Runnable, Object, boolean) InvocationEvent}(source, runnable, null, false)</tt>. |
| * <p> This method throws an <code>IllegalArgumentException</code> |
| * if <code>source</code> is <code>null</code>. |
| * |
| * @param source The <code>Object</code> that originated the event |
| * @param runnable The <code>Runnable</code> whose <code>run</code> |
| * method will be executed |
| * @throws IllegalArgumentException if <code>source</code> is null |
| * |
| * @see #getSource() |
| * @see #InvocationEvent(Object, Runnable, Object, boolean) |
| */ |
| public InvocationEvent(Object source, Runnable runnable) { |
| this(source, runnable, null, false); |
| } |
| |
| /** |
| * Constructs an <code>InvocationEvent</code> with the specified |
| * source which will execute the runnable's <code>run</code> |
| * method when dispatched. If notifier is non-<code>null</code>, |
| * <code>notifyAll()</code> will be called on it |
| * immediately after <code>run</code> has returned or thrown an exception. |
| * <p>An invocation of the form <tt>InvocationEvent(source, |
| * runnable, notifier, catchThrowables)</tt> |
| * behaves in exactly the same way as the invocation of |
| * <tt>{@link #InvocationEvent(Object, int, Runnable, Object, boolean) InvocationEvent}(source, InvocationEvent.INVOCATION_DEFAULT, runnable, notifier, catchThrowables)</tt>. |
| * <p>This method throws an <code>IllegalArgumentException</code> |
| * if <code>source</code> is <code>null</code>. |
| * |
| * @param source The <code>Object</code> that originated |
| * the event |
| * @param runnable The <code>Runnable</code> whose |
| * <code>run</code> method will be |
| * executed |
| * @param notifier The {@code Object} whose <code>notifyAll</code> |
| * method will be called after |
| * <code>Runnable.run</code> has returned or |
| * thrown an exception |
| * @param catchThrowables Specifies whether <code>dispatch</code> |
| * should catch Throwable when executing |
| * the <code>Runnable</code>'s <code>run</code> |
| * method, or should instead propagate those |
| * Throwables to the EventDispatchThread's |
| * dispatch loop |
| * @throws IllegalArgumentException if <code>source</code> is null |
| * |
| * @see #getSource() |
| * @see #InvocationEvent(Object, int, Runnable, Object, boolean) |
| */ |
| public InvocationEvent(Object source, Runnable runnable, Object notifier, |
| boolean catchThrowables) { |
| this(source, INVOCATION_DEFAULT, runnable, notifier, catchThrowables); |
| } |
| |
| /** |
| * Constructs an <code>InvocationEvent</code> with the specified |
| * source and ID which will execute the runnable's <code>run</code> |
| * method when dispatched. If notifier is non-<code>null</code>, |
| * <code>notifyAll</code> will be called on it immediately after |
| * <code>run</code> has returned or thrown an exception. |
| * <p>This method throws an |
| * <code>IllegalArgumentException</code> if <code>source</code> |
| * is <code>null</code>. |
| * |
| * @param source The <code>Object</code> that originated |
| * the event |
| * @param id An integer indicating the type of event. |
| * For information on allowable values, see |
| * the class description for {@link InvocationEvent} |
| * @param runnable The <code>Runnable</code> whose |
| * <code>run</code> method will be executed |
| * @param notifier The <code>Object</code> whose <code>notifyAll</code> |
| * method will be called after |
| * <code>Runnable.run</code> has returned or |
| * thrown an exception |
| * @param catchThrowables Specifies whether <code>dispatch</code> |
| * should catch Throwable when executing the |
| * <code>Runnable</code>'s <code>run</code> |
| * method, or should instead propagate those |
| * Throwables to the EventDispatchThread's |
| * dispatch loop |
| * @throws IllegalArgumentException if <code>source</code> is null |
| * @see #getSource() |
| * @see #getID() |
| */ |
| protected InvocationEvent(Object source, int id, Runnable runnable, |
| Object notifier, boolean catchThrowables) { |
| super(source, id); |
| this.runnable = runnable; |
| this.notifier = notifier; |
| this.catchExceptions = catchThrowables; |
| this.when = System.currentTimeMillis(); |
| } |
| |
| /** |
| * Executes the Runnable's <code>run()</code> method and notifies the |
| * notifier (if any) when <code>run()</code> has returned or thrown an exception. |
| * |
| * @see #isDispatched |
| */ |
| public void dispatch() { |
| try { |
| if (catchExceptions) { |
| try { |
| runnable.run(); |
| } |
| catch (Throwable t) { |
| if (t instanceof Exception) { |
| exception = (Exception) t; |
| } |
| throwable = t; |
| } |
| } |
| else { |
| runnable.run(); |
| } |
| } finally { |
| dispatched = true; |
| |
| if (notifier != null) { |
| synchronized (notifier) { |
| notifier.notifyAll(); |
| } |
| } |
| } |
| } |
| |
| /** |
| * Returns any Exception caught while executing the Runnable's <code>run() |
| * </code> method. |
| * |
| * @return A reference to the Exception if one was thrown; null if no |
| * Exception was thrown or if this InvocationEvent does not |
| * catch exceptions |
| */ |
| public Exception getException() { |
| return (catchExceptions) ? exception : null; |
| } |
| |
| /** |
| * Returns any Throwable caught while executing the Runnable's <code>run() |
| * </code> method. |
| * |
| * @return A reference to the Throwable if one was thrown; null if no |
| * Throwable was thrown or if this InvocationEvent does not |
| * catch Throwables |
| * @since 1.5 |
| */ |
| public Throwable getThrowable() { |
| return (catchExceptions) ? throwable : null; |
| } |
| |
| /** |
| * Returns the timestamp of when this event occurred. |
| * |
| * @return this event's timestamp |
| * @since 1.4 |
| */ |
| public long getWhen() { |
| return when; |
| } |
| |
| /** |
| * Returns {@code true} if the event is dispatched or any exception is |
| * thrown while dispatching, {@code false} otherwise. The method should |
| * be called by a waiting thread that calls the {@code notifier.wait()} method. |
| * Since spurious wakeups are possible (as explained in {@link Object#wait()}), |
| * this method should be used in a waiting loop to ensure that the event |
| * got dispatched: |
| * <pre> |
| * while (!event.isDispatched()) { |
| * notifier.wait(); |
| * } |
| * </pre> |
| * If the waiting thread wakes up without dispatching the event, |
| * the {@code isDispatched()} method returns {@code false}, and |
| * the {@code while} loop executes once more, thus, causing |
| * the awakened thread to revert to the waiting mode. |
| * <p> |
| * If the {@code notifier.notifyAll()} happens before the waiting thread |
| * enters the {@code notifier.wait()} method, the {@code while} loop ensures |
| * that the waiting thread will not enter the {@code notifier.wait()} method. |
| * Otherwise, there is no guarantee that the waiting thread will ever be woken |
| * from the wait. |
| * |
| * @return {@code true} if the event has been dispatched, or any exception |
| * has been thrown while dispatching, {@code false} otherwise |
| * @see #dispatch |
| * @see #notifier |
| * @see #catchExceptions |
| * @since 1.7 |
| */ |
| public boolean isDispatched() { |
| return dispatched; |
| } |
| |
| /** |
| * Returns a parameter string identifying this event. |
| * This method is useful for event-logging and for debugging. |
| * |
| * @return A string identifying the event and its attributes |
| */ |
| public String paramString() { |
| String typeStr; |
| switch(id) { |
| case INVOCATION_DEFAULT: |
| typeStr = "INVOCATION_DEFAULT"; |
| break; |
| default: |
| typeStr = "unknown type"; |
| } |
| return typeStr + ",runnable=" + runnable + ",notifier=" + notifier + |
| ",catchExceptions=" + catchExceptions + ",when=" + when; |
| } |
| } |
