1 /*

     2  * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 /*

    27  * @(#)UUEncoderStream.java   1.3 02/03/27

    28  */

    29 

    30 

    31 

    32 package com.sun.xml.internal.messaging.saaj.packaging.mime.util;

    33 

    34 import java.io.*;

    35 

    36 /**

    37  * This class implements a UUEncoder. It is implemented as

    38  * a FilterOutputStream, so one can just wrap this class around

    39  * any output stream and write bytes into this filter. The Encoding

    40  * is done as the bytes are written out.

    41  *

    42  * @author John Mani

    43  */

    44 

    45 public class UUEncoderStream extends FilterOutputStream {

    46     private byte[] buffer;      // cache of bytes that are yet to be encoded

    47     private int bufsize = 0;    // size of the cache

    48     private boolean wrotePrefix = false;

    49 

    50     protected String name;      // name of file

    51     protected int mode;         // permissions mode

    52 

    53     /**

    54      * Create a UUencoder that encodes the specified input stream

    55      * @param out        the output stream

    56      */

    57     public UUEncoderStream(OutputStream out) {

    58         this(out, "encoder.buf", 644);

    59     }

    60 

    61     /**

    62      * Create a UUencoder that encodes the specified input stream

    63      * @param out        the output stream

    64      * @param name       Specifies a name for the encoded buffer

    65      */

    66     public UUEncoderStream(OutputStream out, String name) {

    67         this(out, name, 644);

    68     }

    69 

    70     /**

    71      * Create a UUencoder that encodes the specified input stream

    72      * @param out        the output stream

    73      * @param name       Specifies a name for the encoded buffer

    74      * @param mode       Specifies permission mode for the encoded buffer

    75      */

    76     public UUEncoderStream(OutputStream out, String name, int mode) {

    77         super(out);

    78         this.name = name;

    79         this.mode = mode;

    80         buffer = new byte[45];

    81     }

    82 

    83     /**

    84      * Set up the buffer name and permission mode.

    85      * This method has any effect only if it is invoked before

    86      * you start writing into the output stream

    87      */

    88     public void setNameMode(String name, int mode) {

    89         this.name = name;

    90         this.mode = mode;

    91     }

    92 

    93     public void write(byte[] b, int off, int len) throws IOException {

    94         for (int i = 0; i < len; i++)

    95             write(b[off + i]);

    96     }

    97 

    98     public void write(byte[] data) throws IOException {

    99         write(data, 0, data.length);

   100     }

   101 

   102     public void write(int c) throws IOException {

   103         /* buffer up characters till we get a line's worth, then encode

   104          * and write them out. Max number of characters allowed per

   105          * line is 45.

   106          */

   107         buffer[bufsize++] = (byte)c;

   108         if (bufsize == 45) {

   109             writePrefix();

   110             encode();

   111             bufsize = 0;

   112         }

   113     }

   114 

   115     public void flush() throws IOException {

   116         if (bufsize > 0) { // If there's unencoded characters in the buffer

   117             writePrefix();

   118             encode();      // .. encode them

   119         }

   120         writeSuffix();

   121         out.flush();

   122     }

   123 

   124     public void close() throws IOException {

   125         flush();

   126         out.close();

   127     }

   128 

   129     /**

   130      * Write out the prefix: "begin <mode> <name>"

   131      */

   132     private void writePrefix() throws IOException {

   133         if (!wrotePrefix) {

   134             PrintStream ps = new PrintStream(out);

   135             ps.println("begin " + mode + " " + name);

   136             ps.flush();

   137             wrotePrefix = true;

   138         }

   139     }

   140 

   141     /**

   142      * Write a single line containing space and the suffix line

   143      * containing the single word "end" (terminated by a newline)

   144      */

   145     private void writeSuffix() throws IOException {

   146         PrintStream ps = new PrintStream(out);

   147         ps.println(" \nend");

   148         ps.flush();

   149     }

   150 

   151     /**

   152      * Encode a line.

   153      * Start off with the character count, followed by the encoded atoms

   154      * and terminate with LF. (or is it CRLF or the local line-terminator ?)

   155      * Take three bytes and encodes them into 4 characters

   156      * If bufsize if not a multiple of 3, the remaining bytes are filled

   157      * with '1'. This insures that the last line won't end in spaces

   158      * and potentiallly be truncated.

   159      */

   160     private void encode() throws IOException {

   161         byte a, b, c;

   162         int c1, c2, c3, c4;

   163         int i = 0;

   164 

   165         // Start off with the count of characters in the line

   166         out.write((bufsize & 0x3f) + ' ');

   167 

   168         while (i < bufsize) {

   169             a = buffer[i++];

   170             if (i < bufsize) {

   171                 b = buffer[i++];

   172                 if (i < bufsize)

   173                     c = buffer[i++];

   174                 else // default c to 1

   175                     c = 1;

   176             }

   177             else { // default b & c to 1

   178                 b = 1;

   179                 c = 1;

   180             }

   181 

   182             c1 = (a >>> 2) & 0x3f;

   183             c2 = ((a << 4) & 0x30) | ((b >>> 4) & 0xf);

   184             c3 = ((b << 2) & 0x3c) | ((c >>> 6) & 0x3);

   185             c4 = c & 0x3f;

   186             out.write(c1 + ' ');

   187             out.write(c2 + ' ');

   188             out.write(c3 + ' ');

   189             out.write(c4 + ' ');

   190         }

   191         // Terminate with LF. (should it be CRLF or local line-terminator ?)

   192         out.write('\n');

   193     }

   194 

   195     /**** begin TEST program *****

   196     public static void main(String argv[]) throws Exception {

   197         FileInputStream infile = new FileInputStream(argv[0]);

   198         UUEncoderStream encoder = new UUEncoderStream(System.out);

   199         int c;

   200 

   201         while ((c = infile.read()) != -1)

   202             encoder.write(c);

   203         encoder.close();

   204     }

   205     **** end TEST program *****/

   206 }