test/jdk/javax/imageio/spi/DeregisterAllSpiTest.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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 * questions.
 */

/*
 * @test
 * @bug 4835841
 * @summary This test verifies that we will able to register new SPI after
 *          deregistration all previously registered SPIs by using
 *          deregisterAll() method
 */

import java.io.IOException;
import java.util.Locale;

import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import javax.imageio.spi.IIORegistry;
import javax.imageio.spi.ImageReaderSpi;
import javax.imageio.spi.ServiceRegistry;
import javax.imageio.stream.ImageInputStream;

public class DeregisterAllSpiTest {

    public DeregisterAllSpiTest() throws Exception {
        ImageReaderSpi BMPSpi = new BMPImageReaderSPI();
        IIORegistry.getDefaultInstance().registerServiceProvider(BMPSpi);

        System.out.println("Reader Format Names available in the registry");
        String formatNames[] = ImageIO.getReaderFormatNames();
        if( formatNames == null || formatNames.length <= 0) {
            throw new RuntimeException("No registered ImageReaders!");
        }
        for (int x=0; x < formatNames.length; x++) {
            System.out.println("format "+formatNames[x]);
        }

        IIORegistry.getDefaultInstance().deregisterAll();

        System.out.println("\nReader Format Names after deregistering all SPIs");
        formatNames = ImageIO.getReaderFormatNames();
        if(formatNames.length == 0) {
            System.out.println("No readers available\n");
        } else {
            throw new RuntimeException("Some providers was not deregistered!");
        }

        IIORegistry.getDefaultInstance().registerServiceProvider(BMPSpi);
        System.out.println("Reader Format Names after re-register of BMP Plugin");
        formatNames = ImageIO.getReaderFormatNames();
        if(formatNames.length == 0) {
            throw new RuntimeException("Unable to register new SPI after deregisterAll()!");
        }
    }


    public static void main(String args[]) throws Exception{
        DeregisterAllSpiTest regis = new DeregisterAllSpiTest();
    }


    public static class BMPImageReaderSPI extends javax.imageio.spi.ImageReaderSpi{

        private static final String vendorName = "Javasoft";

        private static final String version = "2.0";

        private static final String[] names = { "bmp" };

        private static final String[] suffixes = { "bmp" };

        private static final String[] MIMETypes = { "image/x-bmp"};

        private static final String readerClassName =
        "com.sun.imageio.plugins.png.PNGImageReader";

        private static final String[] writerSpiNames = {
            "com.sun.imageio.plugins.png.PNGImageWriterSpi"
        };

        public BMPImageReaderSPI() {
            super(vendorName,
                  version,
                  names,
                  suffixes,
                  MIMETypes,
                  readerClassName,
                  STANDARD_INPUT_TYPE,
                  writerSpiNames,
                  false,
                  null, null,
                  null, null,
                  true,
                  "BMP Native Metadata",
                  "com.sun.imageio.plugins.png.PNGMetadataFormat",
                  null, null
                  );
        }

        public String getDescription(Locale locale) {
            return "Standard BMP image reader";
        }

        public boolean canDecodeInput(Object input) throws IOException {
            if (!(input instanceof ImageInputStream)) {
                return false;
            }

            ImageInputStream stream = (ImageInputStream)input;
            byte[] b = new byte[8];
            stream.mark();
            stream.readFully(b);
            stream.reset();

            return (b[0] == (byte)137 &&
                    b[1] == (byte)80 &&
                    b[2] == (byte)78 &&
                    b[3] == (byte)71 &&
                    b[4] == (byte)13 &&
                    b[5] == (byte)10 &&
                    b[6] == (byte)26 &&
                    b[7] == (byte)10);
        }

        public ImageReader createReaderInstance(Object extension) {
            //return new PNGImageReader(this);
            return null;
        }
        public void onRegistration(ServiceRegistry sr, Class<?> category) {
            System.out.println("\nfrom OnRegistration: BMP plugin Registered\n");
            super.onRegistration(sr, category);
        }

        public void onDeregistration(ServiceRegistry sr, Class<?> category) {
            System.out.println("\nfrom OnDeregistration: BMP plugin De-Registered\n");
            //super.onRegistration(sr, category);
        }
    }
}