/*

 * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.

 * 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.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/*

 * @test

 * @bug 4393174

 * @summary Checks that ImageIO.write(..., ..., File) truncates the file

 */

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.FileOutputStream;

import javax.imageio.ImageIO;

public class ImageIOWriteFile {

    public static void main(String[] args) {

        long length0 = -1L;

        long length1 = -1L;

        try {

            BufferedImage bi =

                new BufferedImage(1, 1, BufferedImage.TYPE_INT_RGB);

            File outFile = File.createTempFile("imageiowritefile", ".tmp");

            // Write image to an empty file

            outFile.delete();

            ImageIO.write(bi, "png", outFile);

            length0 = outFile.length();

            // Write a larger file full of junk

            outFile.delete();

            FileOutputStream fos = new FileOutputStream(outFile);

            for (int i = 0; i < length0*2; i++) {

                fos.write(1);

            }

            fos.close();

            // Write image again

            ImageIO.write(bi, "png", outFile);

            length1 = outFile.length();

            outFile.delete();

        } catch (Exception e) {

            e.printStackTrace();

            throw new RuntimeException("Unexpected exception!");

        }

        if (length0 == 0) {

            throw new RuntimeException("File length is zero!");

        }

        if (length1 != length0) {

            throw new RuntimeException("File length changed!");

        }

    }

}