| /* |
| * Copyright (c) 2000, 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 |
| * @summary Test read method of FileChannel |
| */ |
| |
| import java.io.*; |
| import java.nio.ByteBuffer; |
| import java.nio.CharBuffer; |
| import java.nio.channels.*; |
| import java.nio.channels.FileChannel; |
| import java.util.Random; |
| |
| |
| /** |
| * Testing FileChannel's mapping capabilities. |
| */ |
| |
| public class Read { |
| |
| private static PrintStream err = System.err; |
| |
| private static Random generator = new Random(); |
| |
| private static int CHARS_PER_LINE = File.separatorChar == '/' ? 5 : 6; |
| |
| private static File blah; |
| |
| public static void main(String[] args) throws Exception { |
| StringBuffer sb = new StringBuffer(); |
| sb.setLength(4); |
| |
| blah = File.createTempFile("blah", null); |
| blah.deleteOnExit(); |
| initTestFile(blah); |
| |
| FileInputStream fis = new FileInputStream(blah); |
| FileChannel c = fis.getChannel(); |
| |
| for (int x=0; x<1000; x++) { |
| long offset = x * CHARS_PER_LINE; |
| long expectedResult = offset / CHARS_PER_LINE; |
| offset = expectedResult * CHARS_PER_LINE; |
| ByteBuffer bleck = ByteBuffer.allocateDirect(CHARS_PER_LINE); |
| |
| c.read(bleck); |
| |
| for (int i=0; i<4; i++) { |
| byte aByte = bleck.get(i); |
| sb.setCharAt(i, (char)aByte); |
| } |
| int result = Integer.parseInt(sb.toString()); |
| if (result != expectedResult) { |
| err.println("I expected "+expectedResult); |
| err.println("I got "+ result); |
| throw new Exception("Read test failed"); |
| } |
| } |
| |
| c.close(); |
| fis.close(); |
| blah.delete(); |
| } |
| |
| /** |
| * Creates file blah: |
| * 0000 |
| * 0001 |
| * 0002 |
| * 0003 |
| * . |
| * . |
| * . |
| * 3999 |
| * |
| * Blah extends beyond a single page of memory so that the |
| * ability to index into a file of multiple pages is tested. |
| */ |
| private static void initTestFile(File blah) throws Exception { |
| FileOutputStream fos = new FileOutputStream(blah); |
| BufferedWriter awriter |
| = new BufferedWriter(new OutputStreamWriter(fos, "8859_1")); |
| |
| for(int i=0; i<4000; i++) { |
| String number = new Integer(i).toString(); |
| for (int h=0; h<4-number.length(); h++) |
| awriter.write("0"); |
| awriter.write(""+i); |
| awriter.newLine(); |
| } |
| awriter.flush(); |
| awriter.close(); |
| } |
| } |