test/jdk/java/awt/GraphicsDevice/CheckDisplayModes.java

/*
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 * 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.
 *
 * 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.
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 */

/*
 * @test
 * @key headful
 * @bug 8007146 8213119
 * @summary [macosx] Setting a display mode crashes JDK under VNC
 */
import java.awt.DisplayMode;
import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;

public class CheckDisplayModes {

    public static void main(String[] args) {
        GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
        GraphicsDevice[] allDevices = ge.getScreenDevices();

        for (GraphicsDevice gd : allDevices) {
            System.out.println("Available screen device: " + gd.getIDstring());
        }

        for (GraphicsDevice graphicDevice : allDevices) {
            System.out.println("On screen device " + graphicDevice.getIDstring());
            if (!graphicDevice.isDisplayChangeSupported()) {
                System.err.println("Display mode change is not supported on this host. Test is considered passed.");
                continue;
            }
            DisplayMode defaultDisplayMode = graphicDevice.getDisplayMode();
            System.out.println("Default display mode: " + defaultDisplayMode);
            checkDisplayMode(defaultDisplayMode);
            graphicDevice.setDisplayMode(defaultDisplayMode);

            DisplayMode[] displayModes = graphicDevice.getDisplayModes();
            for (int i = 0; i < displayModes.length; i++) {
                System.out.println("displayModes[" + i + "] = " + displayModes[i]);
            }
            boolean isDefaultDisplayModeIncluded = false;
            for (DisplayMode displayMode : displayModes) {
                System.out.println("Attempting display mode " + displayMode);
                checkDisplayMode(displayMode);
                graphicDevice.setDisplayMode(displayMode);
                if (defaultDisplayMode.equals(displayMode)) {
                    isDefaultDisplayModeIncluded = true;
                }
            }

            if (!isDefaultDisplayModeIncluded) {
                throw new RuntimeException("Default display mode is not included");
            }
        }
    }

    static void checkDisplayMode(DisplayMode displayMode) {
        if (displayMode == null || displayMode.getWidth() <= 1 || displayMode.getHeight() <= 1) {
            throw new RuntimeException("invalid display mode");
        }
    }
}