Quelle SkipTest.java Sprache: JAVA

/*
* Copyright (c) 1998, 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 1.1 98/01/12
* @bug 4022294
* @summary Test bufferedinputstream for data loss during skip
*
*/

import java.io.*;
import java.util.*;

/**
* This class tests to see if bufferinputstream can be reset
* to recover data that was skipped over when the buffer did
* not contain all the bytes to be skipped
*/
public class SkipTest {

    public static void main(String[] args) throws Exception {
        long skipped = 0;

        // Create a tiny buffered stream so it can be easily
        // set up to contain only some of the bytes to skip
        DataSupplier source = new DataSupplier();
        BufferedInputStream in = new BufferedInputStream(source, 4);

        // Set up data to be skipped and recovered
        // the skip must be longer than the buffer size
        in.mark(30);
        while (skipped < 15) {
            skipped += in.skip(15-skipped);
        }
        int nextint = in.read();
        in.reset();

        // Resume reading and see if data was lost
        nextint = in.read();

        if (nextint != 'a')
            throw new RuntimeException("BufferedInputStream skip lost data");
    }
}

class DataSupplier extends InputStream {

    private int aposition=0;

    public int read() {
        return 'x';
    }

    public long skip(long n) {
        aposition += (int) n;
        return n;
    }

    public static final byte[] buffer = {(byte)'a',(byte)'b',(byte)'c',
(byte)'d',(byte)'e',(byte)'f',(byte)'g',(byte)'h',(byte)'i',
(byte)'j',(byte)'k',(byte)'l',(byte)'m',(byte)'n',(byte)'o',
(byte)'p',(byte)'q',(byte)'r',(byte)'s',(byte)'t',(byte)'u',
(byte)'v',(byte)'w',(byte)'x',(byte)'y',(byte)'z'
                                         };

    public int read(byte b[]) throws IOException {
        return read(b, 0, b.length);
    }

    public int read(byte b[], int off, int len) throws IOException {
        if (len > buffer.length) len = buffer.length;
        System.arraycopy(buffer, aposition, b, off, len);
        return len;
    }

}

quality85%

¤ Dauer der Verarbeitung: 0.12 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.