Quadcap Embeddable Server

com/quadcap/io/PaddedOutputStream.java

Go to the documentation of this file.

package com.quadcap.io;

/* Copyright 1997 - 2003 Quadcap Software.  All rights reserved.
 *
 * This software is distributed under the Quadcap Free Software License.
 * This software may be used or modified for any purpose, personal or
 * commercial.  Open Source redistributions are permitted.  Commercial
 * redistribution of larger works derived from, or works which bundle
 * this software requires a "Commercial Redistribution License"; see
 * http://www.quadcap.com/purchase.
 *
 * Redistributions qualify as "Open Source" under  one of the following terms:
 *   
 *    Redistributions are made at no charge beyond the reasonable cost of
 *    materials and delivery.
 *
 *    Redistributions are accompanied by a copy of the Source Code or by an
 *    irrevocable offer to provide a copy of the Source Code for up to three
 *    years at the cost of materials and delivery.  Such redistributions
 *    must allow further use, modification, and redistribution of the Source
 *    Code under substantially the same terms as this license.
 *
 * Redistributions of source code must retain the copyright notices as they
 * appear in each source code file, these license terms, and the
 * disclaimer/limitation of liability set forth as paragraph 6 below.
 *
 * Redistributions in binary form must reproduce this Copyright Notice,
 * these license terms, and the disclaimer/limitation of liability set
 * forth as paragraph 6 below, in the documentation and/or other materials
 * provided with the distribution.
 *
 * The Software is provided on an "AS IS" basis.  No warranty is
 * provided that the Software is free of defects, or fit for a
 * particular purpose.  
 *
 * Limitation of Liability. Quadcap Software shall not be liable
 * for any damages suffered by the Licensee or any third party resulting
 * from use of the Software.
 */

import java.io.*;
import java.security.SecureRandom;

import com.quadcap.util.Debug;
import com.quadcap.util.Util;

/**
 * A filter output stream that zero-pads (on close) to fill the last block
 * of a specified
 * size
 *
 * @author Stan Bailes
 */

public class PaddedOutputStream extends CountedOutputStream {
    int                 blockSize;
    
    public PaddedOutputStream(OutputStream os, int blockSize) {
        super(os);
        this.blockSize = blockSize;
    }

    public void close() throws IOException {
        int c = count;
        byte bytes[] = new byte[blockSize - count % blockSize];
        new SecureRandom().nextBytes(bytes);
        out.write(bytes);
        out.close();
    }
}