/* * Copyright (c) 1997, 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 4027717 @summary Check for correct implementation of RandomAccessFile.skipBytes */ import java.io.*; public class SkipBytes{ /* * doTest attempts to skip num_to_skip bytes in raf starting from position 0. * It also does a read after the skip to check if EOF has been reached * correctly or incorrectly. */ private static void doTest(RandomAccessFile raf, int start, int num_to_skip) throws Exception { raf.seek(start); long cur_ptr = raf.getFilePointer(); int length = (int) raf.length(); System.err.println("\nCurrent pointer = " + cur_ptr + " length = " + length + " num_to_skip = " + num_to_skip); //Do the Skip test int num_skipped = raf.skipBytes(num_to_skip); System.err.println("After skipBytes -- no. skipped = " + num_skipped); // if num_to_skip is negative do the negative skip test if (num_to_skip <= 0) { if (num_skipped != 0){ System.err.println("Negative Skip Test Failed"); throw new RuntimeException("Negative Skip Test Failed"); } else { System.err.println("Negative Skip Test Succeeded"); } } cur_ptr = raf.getFilePointer(); System.err.println("Current pointer = " + cur_ptr); // Check if skip has gone beyond EOF. if (cur_ptr > length) { System.err.println("Past EOF Skip Test Failed"); throw new RuntimeException("Past EOF Skip Test Failed"); } else { System.err.println("Past EOF Skip Test Succeeded"); } // do read test int byte_read = raf.read(); if ( (cur_ptr == length) && (byte_read != -1) ) { System.err.println("byte_read = " + byte_read + " Read Test Failed ......"); throw new RuntimeException("Read Test Failed"); } else { System.err.println("byte_read = " + byte_read + " Read Test Succeeded"); } } public static void main(String[] args) throws Exception { RandomAccessFile raf = new RandomAccessFile("input.txt" , "rw"); try { int length = (int)raf.length(); doTest(raf , 0 , 2*length); doTest(raf , 0 , length); doTest(raf , 0 , length/2); doTest(raf , length/2 , -2); doTest(raf , length , 0); doTest(raf , 0 , -1); } finally{ raf.close(); } } }