Mercurial > jmeCapture

     1 /**

     2  * @(#)DataChunkOutputStream.java  1.1  2011-01-17

     3  *

     4  * Copyright (c) 2008-2011 Werner Randelshofer, Immensee, Switzerland.

     5  * All rights reserved.

     6  *

     7  * You may not use, copy or modify this file, except in compliance with the

     8  * license agreement you entered into with Werner Randelshofer.

     9  * For details see accompanying license terms.

    10  */

    11 package com.aurellem.capture;

    12 

    13 import java.io.*;

    14 

    15 /**

    16  * This output stream filter supports common data types used inside

    17  * of AVI RIFF Data Chunks.

    18  *

    19  * @author Werner Randelshofer

    20  * @version 1.1 2011-01-17 Adds functionality for blocking flush and close.

    21  * <br>1.0.1 2010-04-05 Removed unused constants.

    22  * <br>1.0  2008-08-11 Created.

    23  */

    24 public class DataChunkOutputStream extends FilterOutputStream {

    25 

    26     /**

    27      * The number of bytes written to the data output stream so far. 

    28      * If this counter overflows, it will be wrapped to Integer.MAX_VALUE.

    29      */

    30     protected long written;

    31 

    32     /** Whether flush and close request shall be forwarded to underlying stream.*/

    33     private boolean forwardFlushAndClose;

    34 

    35     public DataChunkOutputStream(OutputStream out) {

    36         this(out,true);

    37     }

    38     public DataChunkOutputStream(OutputStream out, boolean forwardFlushAndClose) {

    39         super(out);

    40         this.forwardFlushAndClose=forwardFlushAndClose;

    41     }

    42 

    43     /**

    44      * Writes an chunk type identifier (4 bytes).

    45      * @param s A string with a length of 4 characters.

    46      */

    47     public void writeType(String s) throws IOException {

    48         if (s.length() != 4) {

    49             throw new IllegalArgumentException("type string must have 4 characters");

    50         }

    51 

    52         try {

    53             out.write(s.getBytes("ASCII"), 0, 4);

    54             incCount(4);

    55         } catch (UnsupportedEncodingException e) {

    56             throw new InternalError(e.toString());

    57         }

    58     }

    59 

    60     /**

    61      * Writes out a <code>byte</code> to the underlying output stream as 

    62      * a 1-byte value. If no exception is thrown, the counter 

    63      * <code>written</code> is incremented by <code>1</code>.

    64      *

    65      * @param      v   a <code>byte</code> value to be written.

    66      * @exception  IOException  if an I/O error occurs.

    67      * @see        java.io.FilterOutputStream#out

    68      */

    69     public final void writeByte(int v) throws IOException {

    70         out.write(v);

    71         incCount(1);

    72     }

    73 

    74     /**

    75      * Writes <code>len</code> bytes from the specified byte array 

    76      * starting at offset <code>off</code> to the underlying output stream. 

    77      * If no exception is thrown, the counter <code>written</code> is 

    78      * incremented by <code>len</code>.

    79      *

    80      * @param      b     the data.

    81      * @param      off   the start offset in the data.

    82      * @param      len   the number of bytes to write.

    83      * @exception  IOException  if an I/O error occurs.

    84      * @see        java.io.FilterOutputStream#out

    85      */

    86     @Override

    87     public synchronized void write(byte b[], int off, int len)

    88             throws IOException {

    89         out.write(b, off, len);

    90         incCount(len);

    91     }

    92 

    93     /**

    94      * Writes the specified byte (the low eight bits of the argument 

    95      * <code>b</code>) to the underlying output stream. If no exception 

    96      * is thrown, the counter <code>written</code> is incremented by 

    97      * <code>1</code>.

    98      * <p>

    99      * Implements the <code>write</code> method of <code>OutputStream</code>.

   100      *

   101      * @param      b   the <code>byte</code> to be written.

   102      * @exception  IOException  if an I/O error occurs.

   103      * @see        java.io.FilterOutputStream#out

   104      */

   105     @Override

   106     public synchronized void write(int b) throws IOException {

   107         out.write(b);

   108         incCount(1);

   109     }

   110 

   111     /**

   112      * Writes an <code>int</code> to the underlying output stream as four

   113      * bytes, high byte first. If no exception is thrown, the counter 

   114      * <code>written</code> is incremented by <code>4</code>.

   115      *

   116      * @param      v   an <code>int</code> to be written.

   117      * @exception  IOException  if an I/O error occurs.

   118      * @see        java.io.FilterOutputStream#out

   119      */

   120     public void writeInt(int v) throws IOException {

   121         out.write((v >>> 0) & 0xff);

   122         out.write((v >>> 8) & 0xff);

   123         out.write((v >>> 16) & 0xff);

   124         out.write((v >>> 24) & 0xff);

   125         incCount(4);

   126     }

   127 

   128     /**

   129      * Writes an unsigned 32 bit integer value.

   130      * 

   131      * @param v The value

   132      * @throws java.io.IOException

   133      */

   134     public void writeUInt(long v) throws IOException {

   135         out.write((int) ((v >>> 0) & 0xff));

   136         out.write((int) ((v >>> 8) & 0xff));

   137         out.write((int) ((v >>> 16) & 0xff));

   138         out.write((int) ((v >>> 24) & 0xff));

   139         incCount(4);

   140     }

   141 

   142     /**

   143      * Writes a signed 16 bit integer value.

   144      * 

   145      * @param v The value

   146      * @throws java.io.IOException

   147      */

   148     public void writeShort(int v) throws IOException {

   149         out.write((int) ((v >>> 0) & 0xff));

   150         out.write((int) ((v >> 8) & 0xff));

   151         incCount(2);

   152     }

   153 

   154     public void writeLong(long v) throws IOException {

   155         out.write((int) (v >>> 0) & 0xff);

   156         out.write((int) (v >>> 8) & 0xff);

   157         out.write((int) (v >>> 16) & 0xff);

   158         out.write((int) (v >>> 24) & 0xff);

   159         out.write((int) (v >>> 32) & 0xff);

   160         out.write((int) (v >>> 40) & 0xff);

   161         out.write((int) (v >>> 48) & 0xff);

   162         out.write((int) (v >>> 56) & 0xff);

   163         incCount(8);

   164     }

   165 

   166     public void writeUShort(int v) throws IOException {

   167         out.write((int) ((v >>> 0) & 0xff));

   168         out.write((int) ((v >> 8) & 0xff));

   169         incCount(2);

   170     }

   171 

   172     /**

   173      * Increases the written counter by the specified value

   174      * until it reaches Long.MAX_VALUE.

   175      */

   176     protected void incCount(int value) {

   177         long temp = written + value;

   178         if (temp < 0) {

   179             temp = Long.MAX_VALUE;

   180         }

   181         written = temp;

   182     }

   183 

   184     /**

   185      * Returns the current value of the counter <code>written</code>, 

   186      * the number of bytes written to this data output stream so far.

   187      * If the counter overflows, it will be wrapped to Integer.MAX_VALUE.

   188      *

   189      * @return  the value of the <code>written</code> field.

   190      * @see     java.io.DataOutputStream#written

   191      */

   192     public final long size() {

   193         return written;

   194     }

   195     

   196     /**

   197      * Sets the value of the counter <code>written</code> to 0.

   198      */

   199     public void clearCount() {

   200         written = 0;

   201     }

   202 

   203     @Override

   204     public void close() throws IOException {

   205         if (forwardFlushAndClose) {

   206         super.close();

   207         }

   208     }

   209     

   210     @Override

   211     public void flush() throws IOException {

   212         if (forwardFlushAndClose) {

   213         super.flush();

   214         }

   215     }

   216 

   217 }
author	Robert McIntyre <rlm@mit.edu>
date	Tue, 25 Oct 2011 12:03:01 -0700
parents	a92de00f0414
children