/*
* This file is part of muCommander, http://www.mucommander.com
* Copyright (C) 2002-2016 Maxence Bernard
*
* muCommander is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* muCommander 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package com.mucommander.commons.io;
import java.io.IOException;
import java.io.OutputStream;
/**
* <code>BoundedOutputStream</code> is an <code>OutputStream</code> that has a set limit to the number of bytes that can
* be written to it. When that limit is reached, <code>write</code> methods throw a {@link StreamOutOfBoundException}.
*
* @author Maxence Bernard
* @see BoundedInputStream
* @see StreamOutOfBoundException
*/
public class BoundedOutputStream extends FilteredOutputStream implements Bounded {
protected long totalWritten;
protected long allowedBytes;
/**
* Creates a new <code>BoundedInputStream</code> over the specified stream, allowing a maximum of
* <code>allowedBytes</code> to be written to it. If <code>allowedBytes</code> is equal to <code>-1</code>, this
* stream is not bounded and acts as a normal stream.
*
* @param out the stream to be bounded
* @param allowedBytes the total number of bytes that are allowed to written, <code>-1</code> for no limit
*/
public BoundedOutputStream(OutputStream out, long allowedBytes) {
super(out);
this.allowedBytes = allowedBytes;
}
////////////////////////////
// Bounded implementation //
////////////////////////////
public synchronized long getAllowedBytes() {
return allowedBytes;
}
public synchronized long getProcessedBytes() {
return totalWritten;
}
public synchronized long getRemainingBytes() {
return allowedBytes<=-1?Long.MAX_VALUE:allowedBytes-totalWritten;
}
////////////////////////
// Overridden methods //
////////////////////////
@Override
public synchronized void write(int b) throws IOException {
if(getRemainingBytes()==0)
throw new StreamOutOfBoundException(allowedBytes);
out.write(b);
totalWritten++;
}
@Override
public synchronized void write(byte[] b) throws IOException {
write(b, 0, b.length);
}
@Override
public synchronized void write(byte[] b, int off, int len) throws IOException {
int canWrite = (int)Math.min(getRemainingBytes(), len);
if(canWrite==0)
throw new StreamOutOfBoundException(allowedBytes);
out.write(b, off, canWrite);
totalWritten += canWrite;
}
}