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/*
* 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
* @bug 4862411
* @summary Test positional write method of FileChannel
* @key randomness
*/
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 positional write method.
*/
public class Pwrite {
private static Random generator = new Random();
private static File blah;
public static void main(String[] args) throws Exception {
genericTest();
testUnwritableChannel();
}
// This test for bug 4862411
private static void testUnwritableChannel() throws Exception {
File blah = File.createTempFile("blah2", null);
blah.deleteOnExit();
FileOutputStream fos = new FileOutputStream(blah);
fos.write(new byte[128]);
fos.close();
FileInputStream fis = new FileInputStream(blah);
FileChannel fc = fis.getChannel();
try {
fc.write(ByteBuffer.allocate(256),1);
throw new RuntimeException("Expected exception not thrown");
} catch(NonWritableChannelException e) {
// Correct result
} finally {
fc.close();
blah.delete();
}
}
private static void genericTest() throws Exception {
StringBuffer sb = new StringBuffer();
sb.setLength(4);
blah = File.createTempFile("blah", null);
blah.deleteOnExit();
initTestFile(blah);
RandomAccessFile raf = new RandomAccessFile(blah, "rw");
FileChannel c = raf.getChannel();
for (int x=0; x<100; x++) {
long offset = generator.nextInt(1000);
ByteBuffer bleck = ByteBuffer.allocateDirect(4);
// Write known sequence out
for (byte i=0; i<4; i++) {
bleck.put(i);
}
bleck.flip();
long originalPosition = c.position();
int totalWritten = 0;
while (totalWritten < 4) {
int written = c.write(bleck, offset);
if (written < 0)
throw new Exception("Read failed");
totalWritten += written;
}
long newPosition = c.position();
// Ensure that file pointer position has not changed
if (originalPosition != newPosition)
throw new Exception("File position modified");
// Attempt to read sequence back in
bleck = ByteBuffer.allocateDirect(4);
originalPosition = c.position();
int totalRead = 0;
while (totalRead < 4) {
int read = c.read(bleck, offset);
if (read < 0)
throw new Exception("Read failed");
totalRead += read;
}
newPosition = c.position();
// Ensure that file pointer position has not changed
if (originalPosition != newPosition)
throw new Exception("File position modified");
for (byte i=0; i<4; i++) {
if (bleck.get(i) != i)
throw new Exception("Write test failed");
}
}
c.close();
raf.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();
}
}
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