/* ====================================================================
* Trove - Copyright (c) 1999-2000 Walt Disney Internet Group
* ====================================================================
* The Tea Software License, Version 1.1
*
* Copyright (c) 2000 Walt Disney Internet Group. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Walt Disney Internet Group (http://opensource.go.com/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Tea", "TeaServlet", "Kettle", "Trove" and "BeanDoc" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact opensource@dig.com.
*
* 5. Products derived from this software may not be called "Tea",
* "TeaServlet", "Kettle" or "Trove", nor may "Tea", "TeaServlet",
* "Kettle", "Trove" or "BeanDoc" appear in their name, without prior
* written permission of the Walt Disney Internet Group.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE WALT DISNEY INTERNET GROUP OR ITS
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* For more information about Tea, please see http://opensource.go.com/.
*/
package com.go.trove.io;
import java.io.OutputStream;
import java.io.File;
import java.io.RandomAccessFile;
import java.io.IOException;
/******************************************************************************
* A ByteData implementation that reads the contents of a file.
*
* @author Brian S O'Neill
* @version
* <!--$$Revision:--> 19 <!-- $-->, <!--$$JustDate:--> 00/12/06 <!-- $-->
*/
public class FileByteData implements ByteData {
private static final Object NULL = new Object();
private File mFile;
// Thread-local reference to a RandomAccessFile.
private ThreadLocal mRAF = new ThreadLocal();
public FileByteData(File file) {
mFile = file;
// Open here so that if file isn't found, error is logged earlier.
open();
}
public long getByteCount() throws IOException {
// Keep file open to ensure that length doesn't change between call to
// getByteCount and writeTo.
RandomAccessFile raf = open();
if (raf == null) {
return 0;
}
else {
return raf.length();
}
}
public void writeTo(OutputStream out) throws IOException {
RandomAccessFile raf = open();
if (raf == null) {
return;
}
try {
long length = raf.length();
int bufSize;
if (length > 4000) {
bufSize = 4000;
}
else {
bufSize = (int)length;
}
byte[] inputBuffer = new byte[bufSize];
raf.seek(0);
int readAmount;
while ((readAmount = raf.read(inputBuffer, 0, bufSize)) > 0) {
out.write(inputBuffer, 0, readAmount);
}
}
finally {
try {
finalize();
}
catch (IOException e) {
}
}
}
public void reset() throws IOException {
Object obj = mRAF.get();
try {
if (obj instanceof RandomAccessFile) {
((RandomAccessFile)obj).close();
}
}
finally {
mRAF.set(null);
}
}
protected final void finalize() throws IOException {
reset();
}
private RandomAccessFile open() {
Object obj = mRAF.get();
if (obj instanceof RandomAccessFile) {
return (RandomAccessFile)obj;
}
else if (obj == NULL) {
return null;
}
RandomAccessFile raf = null;
try {
raf = new RandomAccessFile(mFile, "r");
mRAF.set(raf);
}
catch (IOException e) {
mRAF.set(NULL);
Thread t = Thread.currentThread();
t.getThreadGroup().uncaughtException(t, e);
}
return raf;
}
}