Loads a JPEG image using Sun's loader in preference to the standard one, if it's available. - Java 2D Graphics

Java examples for 2D Graphics:Image Load

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Description

Loads a JPEG image using Sun's loader in preference to the standard one, if it's available.

Demo Code

/*//from   w  w  w  .  j av a 2  s .c  o  m
This file is part of leafdigital util.

util is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

util 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 for more details.

You should have received a copy of the GNU General Public License
along with util.  If not, see <http://www.gnu.org/licenses/>.

Copyright 2011 Samuel Marshall.
 */
import java.awt.*;
import java.awt.font.FontRenderContext;
import java.awt.image.BufferedImage;
import java.io.*;
import java.lang.reflect.Method;
import java.net.URL;
import javax.swing.JPanel;

public class Main{
    /** Used only if we need a component for MediaTracker */
    public static JPanel pStupid = null;
    /**
     * Loads a JPEG image using Sun's loader in preference to  the standard one,
     * if it's available. (Probably there is no point in doing this any more...)
     * @param is Input stream
     * @return Image
     * @throws IOException
     */
    public static Image loadJPEG(InputStream is) throws IOException {
        // If Sun's codec is present, use it (for some ungodly reason, it's twice
        // as fast as the normal loader). Do reflection to avoid causing link errors
        // if it's unavailable
        try {
            Class<?> cJPEGCodec = Class
                    .forName("com.sun.image.codec.jpeg.JPEGCodec");
            Method m = cJPEGCodec.getDeclaredMethod("createJPEGDecoder",
                    InputStream.class);
            Object decoder = m.invoke(null, is);
            m = decoder.getClass().getDeclaredMethod(
                    "decodeAsBufferedImage");
            return (Image) m.invoke(decoder);
        } catch (Exception e) {
            return loadOther(IOUtils.loadBytes(is));
        }
    }
    /**
     * Loads an image that isn't JPEG (with default Java loader).
     * @param data
     * @return Image (ready for display)
     */
    public static Image loadOther(byte[] data) {
        Image iReturn;
        if (pStupid == null)
            pStupid = new JPanel();
        iReturn = Toolkit.getDefaultToolkit().createImage(data);
        waitImage(iReturn);
        return iReturn;
    }
    private static void waitImage(Image i) {
        MediaTracker mt = new MediaTracker(pStupid);
        mt.addImage(i, 1);
        try {
            mt.waitForAll();
        } catch (InterruptedException e2) {
        }
    }
}

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