/* * 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; } }