jdk/src/java.desktop/share/classes/java/awt/DisplayMode.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 *
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package java.awt;

import java.lang.annotation.Native;

/**
 * The {@code DisplayMode} class encapsulates the bit depth, height,
 * width, and refresh rate of a {@code GraphicsDevice}. The ability to
 * change graphics device's display mode is platform- and
 * configuration-dependent and may not always be available
 * (see {@link GraphicsDevice#isDisplayChangeSupported}).
 * <p>
 * For more information on full-screen exclusive mode API, see the
 * <a href="http://docs.oracle.com/javase/tutorial/extra/fullscreen/index.html">
 * Full-Screen Exclusive Mode API Tutorial</a>.
 *
 * @see GraphicsDevice
 * @see GraphicsDevice#isDisplayChangeSupported
 * @see GraphicsDevice#getDisplayModes
 * @see GraphicsDevice#setDisplayMode
 * @author Michael Martak
 * @since 1.4
 */

public final class DisplayMode {

    private Dimension size;
    private int bitDepth;
    private int refreshRate;

    /**
     * Create a new display mode object with the supplied parameters.
     * @param width the width of the display, in pixels
     * @param height the height of the display, in pixels
     * @param bitDepth the bit depth of the display, in bits per
     *        pixel.  This can be {@code BIT_DEPTH_MULTI} if multiple
     *        bit depths are available.
     * @param refreshRate the refresh rate of the display, in hertz.
     *        This can be {@code REFRESH_RATE_UNKNOWN} if the
     *        information is not available.
     * @see #BIT_DEPTH_MULTI
     * @see #REFRESH_RATE_UNKNOWN
     */
    public DisplayMode(int width, int height, int bitDepth, int refreshRate) {
        this.size = new Dimension(width, height);
        this.bitDepth = bitDepth;
        this.refreshRate = refreshRate;
    }

    /**
     * Returns the height of the display, in pixels.
     * @return the height of the display, in pixels
     */
    public int getHeight() {
        return size.height;
    }

    /**
     * Returns the width of the display, in pixels.
     * @return the width of the display, in pixels
     */
    public int getWidth() {
        return size.width;
    }

    /**
     * Value of the bit depth if multiple bit depths are supported in this
     * display mode.
     * @see #getBitDepth
     */
    @Native public static final int BIT_DEPTH_MULTI = -1;

    /**
     * Returns the bit depth of the display, in bits per pixel.  This may be
     * {@code BIT_DEPTH_MULTI} if multiple bit depths are supported in
     * this display mode.
     *
     * @return the bit depth of the display, in bits per pixel.
     * @see #BIT_DEPTH_MULTI
     */
    public int getBitDepth() {
        return bitDepth;
    }

    /**
     * Value of the refresh rate if not known.
     * @see #getRefreshRate
     */
    @Native public static final int REFRESH_RATE_UNKNOWN = 0;

    /**
     * Returns the refresh rate of the display, in hertz.  This may be
     * {@code REFRESH_RATE_UNKNOWN} if the information is not available.
     *
     * @return the refresh rate of the display, in hertz.
     * @see #REFRESH_RATE_UNKNOWN
     */
    public int getRefreshRate() {
        return refreshRate;
    }

    /**
     * Returns whether the two display modes are equal.
     *
     * @param  dm the display mode to compare to
     * @return whether the two display modes are equal
     */
    public boolean equals(DisplayMode dm) {
        if (dm == null) {
            return false;
        }
        return (getHeight() == dm.getHeight()
            && getWidth() == dm.getWidth()
            && getBitDepth() == dm.getBitDepth()
            && getRefreshRate() == dm.getRefreshRate());
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean equals(Object dm) {
        if (dm instanceof DisplayMode) {
            return equals((DisplayMode)dm);
        } else {
            return false;
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public int hashCode() {
        return getWidth() + getHeight() + getBitDepth() * 7
            + getRefreshRate() * 13;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String toString() {
        return getWidth() + "x" + getHeight() + "x" +
               (getBitDepth() > 0 ? getBitDepth() + "bpp": "[Multi depth]")
               + "@" + (getRefreshRate() > 0 ? getRefreshRate() + "Hz" :
               "[Unknown refresh rate]");
    }
}