/*

 * 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

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 */

/* @test

   @bug 4334846

   @summary Make sure zip file comments of various sizes can be written.

   @author Martin Buchholz

 */

import java.io.*;

import java.util.zip.ZipEntry;

import java.util.zip.ZipFile;

import java.util.zip.ZipOutputStream;

public class Comment {

    private static final String entryName = "entryName";

    private static final String entryContents = "entryContents";

    private static final int commentMaxLength = 0xFFFF;

    private static final int [] commentLengths

        = { 0, 1, 32768, commentMaxLength - 1, commentMaxLength };

    public static void main(String argv[])

        throws Exception

    {

        for (int i = 0; i < commentLengths.length; ++i) {

            int commentLength = commentLengths[i];

            String comment = buildComment(commentLength);

            String name = "Test" + commentLength + ".zip";

            writeZipFile(name, comment);

            verifyZipFile(name, comment);

            new File(name).delete();

            System.out.println(commentLength + ": successful");

        }

    }

    private static void writeZipFile(String name, String comment)

        throws IOException

    {

        ZipOutputStream zos = new ZipOutputStream(new FileOutputStream(name));

    }

    private static void verifyZipFile(String name, String comment)

        throws Exception

    {

        // Check that Zip entry was correctly written.

        ZipFile zipFile = new ZipFile(name);

        ZipEntry zipEntry = zipFile.getEntry(entryName);

        InputStream is = zipFile.getInputStream(zipEntry);

        String result = new DataInputStream(is).readUTF();

        if (!result.equals(entryContents))

            throw new Exception("Entry contents corrupted");

        // Check that comment length was correctly written.

        RandomAccessFile file = new RandomAccessFile(name, "r");

        file.seek(file.length() - comment.length()

                  - ZipFile.ENDHDR + ZipFile.ENDCOM);

        int b1 = file.readUnsignedByte();

        int b2 = file.readUnsignedByte();

        if (b1 + (b2 << 8) != comment.length())

            throw new Exception("Zip file comment length corrupted");

        // Check that comment was correctly written.

        file.seek(file.length() - comment.length());

        byte [] bytes = new byte [comment.length()];

        file.readFully(bytes);

        if (! comment.equals(new String(bytes, "UTF8")))

            throw new Exception("Zip file comment corrupted");

    }

    private static String buildComment(int length) {

        StringBuffer result = new StringBuffer();

        while (result.length() < length) {

            /* Endhdr is 22 bytes long, so this pattern makes it easy

             * to see if it is copied correctly */

            result.append("abcdefghijklmnopqrstuvABCDEFGHIJKLMNOPQRSTUV");

        }

        String string = result.toString();

        string = string.substring(string.length() - length);

        return string;

    }

}