/*

 * Copyright (c) 2010, 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 6720170

 * @summary check for ByteArrayInputStream.skip

 */

import java.io.*;

public class Skip {

    private static void dotest(InputStream in, int curpos, long total,

                               long toskip, long expected)

        throws Exception

    {

        System.err.println("\nCurrently at pos = " + curpos +

                           "\nTotal bytes in the stream = " + total +

                           "\nNumber of bytes to skip = " + toskip +

                           "\nNumber of bytes that should be skipped = " +

                           expected);

        // position to curpos; EOF if negative

        in.reset();

        int avail = curpos >= 0 ? curpos : in.available();

        long n = in.skip(avail);

        if (n != avail) {

            throw new RuntimeException("Unexpected number of bytes skipped = " + n);

        }

        long skipped = in.skip(toskip);

        System.err.println("actual number skipped: "+ skipped);

        if (skipped != expected) {

            throw new RuntimeException("Unexpected number of bytes skipped = " + skipped);

        }

    }

    public static void main(String argv[]) throws Exception {

        int total = 1024;

        ByteArrayInputStream in = new ByteArrayInputStream(new byte[total]);

        /* test for skip */

        dotest(in,  0, total, 23, 23);

        dotest(in,  10, total, 23, 23);

        /* test for negative skip */

        dotest(in,  0, total, -23,  0);

        /* check for skip after EOF */

        dotest(in, -1, total,  20,  0);

        /* check for skip beyond EOF starting from before EOF */

        dotest(in,  0, total, total+20, total);

        /* check for skip if the pos + toskip causes integer overflow */

        dotest(in, 10, total, Long.MAX_VALUE, total-10);

    }

}