src/share/jaxws_classes/com/sun/xml/internal/messaging/saaj/packaging/mime/util/QPDecoderStream.java

Thu, 31 Aug 2017 15:18:52 +0800

author
aoqi
date
Thu, 31 Aug 2017 15:18:52 +0800
changeset 637
9c07ef4934dd
parent 368
0989ad8c0860
parent 0
373ffda63c9a
permissions
-rw-r--r--

merge

     1 /*
     2  * Copyright (c) 1997, 2012, 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  */
    26 /*
    27  * @(#)QPDecoderStream.java   1.9 02/04/02
    28  */
    32 package com.sun.xml.internal.messaging.saaj.packaging.mime.util;
    34 import java.io.*;
    36 /**
    37  * This class implements a QP Decoder. It is implemented as
    38  * a FilterInputStream, so one can just wrap this class around
    39  * any input stream and read bytes from this filter. The decoding
    40  * is done as the bytes are read out.
    41  *
    42  * @author John Mani
    43  */
    45 public class QPDecoderStream extends FilterInputStream {
    46     protected byte[] ba = new byte[2];
    47     protected int spaces = 0;
    49     /**
    50      * Create a Quoted Printable decoder that decodes the specified
    51      * input stream.
    52      * @param in        the input stream
    53      */
    54     public QPDecoderStream(InputStream in) {
    55         super(new PushbackInputStream(in, 2)); // pushback of size=2
    56     }
    58     /**
    59      * Read the next decoded byte from this input stream. The byte
    60      * is returned as an <code>int</code> in the range <code>0</code>
    61      * to <code>255</code>. If no byte is available because the end of
    62      * the stream has been reached, the value <code>-1</code> is returned.
    63      * This method blocks until input data is available, the end of the
    64      * stream is detected, or an exception is thrown.
    65      *
    66      * @return     the next byte of data, or <code>-1</code> if the end of the
    67      *             stream is reached.
    68      * @exception  IOException  if an I/O error occurs.
    69      */
    70     public int read() throws IOException {
    71         if (spaces > 0) {
    72             // We have cached space characters, return one
    73             spaces--;
    74             return ' ';
    75         }
    77         int c = in.read();
    79         if (c == ' ') {
    80             // Got space, keep reading till we get a non-space char
    81             while ((c = in.read()) == ' ')
    82                 spaces++;
    84             if (c == '\r' || c == '\n' || c == -1)
    85                 // If the non-space char is CR/LF/EOF, the spaces we got
    86                 // so far is junk introduced during transport. Junk 'em.
    87                 spaces = 0;
    88             else {
    89                 // The non-space char is NOT CR/LF, the spaces are valid.
    90                 ((PushbackInputStream)in).unread(c);
    91                 c = ' ';
    92             }
    93             return c; // return either <SPACE> or <CR/LF>
    94         }
    95         else if (c == '=') {
    96             // QP Encoded atom. Decode the next two bytes
    97             int a = in.read();
    99             if (a == '\n') {
   100                 /* Hmm ... not really confirming QP encoding, but lets
   101                  * allow this as a LF terminated encoded line .. and
   102                  * consider this a soft linebreak and recurse to fetch
   103                  * the next char.
   104                  */
   105                 return read();
   106             } else if (a == '\r') {
   107                 // Expecting LF. This forms a soft linebreak to be ignored.
   108                 int b = in.read();
   109                 if (b != '\n')
   110                     /* Not really confirming QP encoding, but
   111                      * lets allow this as well.
   112                      */
   113                     ((PushbackInputStream)in).unread(b);
   114                 return read();
   115             } else if (a == -1) {
   116                 // Not valid QP encoding, but we be nice and tolerant here !
   117                 return -1;
   118             } else {
   119                 ba[0] = (byte)a;
   120                 ba[1] = (byte)in.read();
   121                 try {
   122                     return ASCIIUtility.parseInt(ba, 0, 2, 16);
   123                 } catch (NumberFormatException nex) {
   124                     /*
   125                     System.err.println(
   126                         "Illegal characters in QP encoded stream: " +
   127                         ASCIIUtility.toString(ba, 0, 2)
   128                     );
   129                     */
   131                     ((PushbackInputStream)in).unread(ba);
   132                     return c;
   133                 }
   134             }
   135         }
   136         return c;
   137     }
   139     /**
   140      * Reads up to <code>len</code> decoded bytes of data from this input stream
   141      * into an array of bytes. This method blocks until some input is
   142      * available.
   143      * <p>
   144      *
   145      * @param      buf   the buffer into which the data is read.
   146      * @param      off   the start offset of the data.
   147      * @param      len   the maximum number of bytes read.
   148      * @return     the total number of bytes read into the buffer, or
   149      *             <code>-1</code> if there is no more data because the end of
   150      *             the stream has been reached.
   151      * @exception  IOException  if an I/O error occurs.
   152      */
   153     public int read(byte[] buf, int off, int len) throws IOException {
   154         int i, c;
   155         for (i = 0; i < len; i++) {
   156             if ((c = read()) == -1) {
   157                 if (i == 0) // At end of stream, so we should
   158                     i = -1; // return -1 , NOT 0.
   159                 break;
   160             }
   161             buf[off+i] = (byte)c;
   162         }
   163         return i;
   164     }
   166     /**
   167      * Tests if this input stream supports marks. Currently this class
   168      * does not support marks
   169      */
   170     public boolean markSupported() {
   171         return false;
   172     }
   174     /**
   175      * Returns the number of bytes that can be read from this input
   176      * stream without blocking. The QP algorithm does not permit
   177      * a priori knowledge of the number of bytes after decoding, so
   178      * this method just invokes the <code>available</code> method
   179      * of the original input stream.
   180      */
   181     public int available() throws IOException {
   182         // This is bogus ! We don't really know how much
   183         // bytes are available *after* decoding
   184         return in.available();
   185     }
   187     /**** begin TEST program
   188     public static void main(String argv[]) throws Exception {
   189         FileInputStream infile = new FileInputStream(argv[0]);
   190         QPDecoderStream decoder = new QPDecoderStream(infile);
   191         int c;
   193         while ((c = decoder.read()) != -1)
   194             System.out.print((char)c);
   195         System.out.println();
   196     }
   197     *** end TEST program ****/
   198 }

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