src/java.desktop/share/classes/java/awt/SentEvent.java

/*
 * Copyright (c) 2000, 2021, 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
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package java.awt;

import java.io.Serial;

import sun.awt.AppContext;
import sun.awt.SunToolkit;

/**
 * A wrapping tag for a nested AWTEvent which indicates that the event was
 * sent from another AppContext. The destination AppContext should handle the
 * event even if it is currently blocked waiting for a SequencedEvent or
 * another SentEvent to be handled.
 *
 * @author David Mendenhall
 */
class SentEvent extends AWTEvent implements ActiveEvent {

    /**
     * Use serialVersionUID from JDK 1.6 for interoperability.
     */
    @Serial
    private static final long serialVersionUID = -383615247028828931L;

    static final int ID =
        java.awt.event.FocusEvent.FOCUS_LAST + 2;

    boolean dispatched;
    private AWTEvent nested;
    @SuppressWarnings("serial") // Not statically typed as Serializable
    private AppContext toNotify;

    SentEvent() {
        this(null);
    }
    SentEvent(AWTEvent nested) {
        this(nested, null);
    }
    SentEvent(AWTEvent nested, AppContext toNotify) {
        super((nested != null)
                  ? nested.getSource()
                  : Toolkit.getDefaultToolkit(),
              ID);
        this.nested = nested;
        this.toNotify = toNotify;
    }

    public void dispatch() {
        try {
            if (nested != null) {
                Toolkit.getEventQueue().dispatchEvent(nested);
            }
        } finally {
            dispatched = true;
            if (toNotify != null) {
                SunToolkit.postEvent(toNotify, new SentEvent());
            }
            synchronized (this) {
                notifyAll();
            }
        }
    }
    final void dispose() {
        dispatched = true;
        if (toNotify != null) {
            SunToolkit.postEvent(toNotify, new SentEvent());
        }
        synchronized (this) {
            notifyAll();
        }
    }
}