ReadUnsignedIntTest.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
 * @bug 4949609
 * @summary Tests that the readUnsignedInt returns the positive value
 */

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.IOException;

import javax.imageio.ImageIO;
import javax.imageio.stream.ImageInputStream;

public class ReadUnsignedIntTest {

    public static void main(String[] args) throws IOException {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        DataOutputStream dos = new DataOutputStream(baos);

        dos.writeInt(1);
        dos.writeInt(0x7fffffff);
        dos.writeInt(0x8fffffff);
        dos.writeInt(0xffffffff);

        dos.close();

        ByteArrayInputStream bais =
            new ByteArrayInputStream(baos.toByteArray());
        ImageInputStream iis = ImageIO.createImageInputStream(bais);
        for (int i=0; i<4; i++) {
            long res = iis.readUnsignedInt();
            if (res <= 0) {
                throw new RuntimeException("Negative number was read: "+
                                           Long.toString(res, 16));
            }
        }
    }
}