aoqi@0: /*
aoqi@0:  * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.  Oracle designates this
aoqi@0:  * particular file as subject to the "Classpath" exception as provided
aoqi@0:  * by Oracle in the LICENSE file that accompanied this code.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  */
aoqi@0: 
aoqi@0: /*
aoqi@0:  * @(#)QDecoderStream.java    1.5 02/03/27
aoqi@0:  */
aoqi@0: 
aoqi@0: 
aoqi@0: 
aoqi@0: package com.sun.xml.internal.messaging.saaj.packaging.mime.util;
aoqi@0: 
aoqi@0: import java.io.IOException;
aoqi@0: import java.io.InputStream;
aoqi@0: 
aoqi@0: /**
aoqi@0:  * This class implements a Q Decoder as defined in RFC 2047
aoqi@0:  * for decoding MIME headers. It subclasses the QPDecoderStream class.
aoqi@0:  *
aoqi@0:  * @author John Mani
aoqi@0:  */
aoqi@0: 
aoqi@0: public class QDecoderStream extends QPDecoderStream {
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Create a Q-decoder that decodes the specified input stream.
aoqi@0:      * @param in        the input stream
aoqi@0:      */
aoqi@0:     public QDecoderStream(InputStream in) {
aoqi@0:         super(in);
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Read the next decoded byte from this input stream. The byte
aoqi@0:      * is returned as an <code>int</code> in the range <code>0</code>
aoqi@0:      * to <code>255</code>. If no byte is available because the end of
aoqi@0:      * the stream has been reached, the value <code>-1</code> is returned.
aoqi@0:      * This method blocks until input data is available, the end of the
aoqi@0:      * stream is detected, or an exception is thrown.
aoqi@0:      *
aoqi@0:      * @return     the next byte of data, or <code>-1</code> if the end of the
aoqi@0:      *             stream is reached.
aoqi@0:      * @exception  IOException  if an I/O error occurs.
aoqi@0:      */
aoqi@0:     public int read() throws IOException {
aoqi@0:         int c = in.read();
aoqi@0: 
aoqi@0:         if (c == '_') // Return '_' as ' '
aoqi@0:             return ' ';
aoqi@0:         else if (c == '=') {
aoqi@0:             // QP Encoded atom. Get the next two bytes ..
aoqi@0:             ba[0] = (byte)in.read();
aoqi@0:             ba[1] = (byte)in.read();
aoqi@0:             // .. and decode them
aoqi@0:             try {
aoqi@0:                 return ASCIIUtility.parseInt(ba, 0, 2, 16);
aoqi@0:             } catch (NumberFormatException nex) {
aoqi@0:                 throw new IOException("Error in QP stream " + nex.getMessage());
aoqi@0:             }
aoqi@0:         } else
aoqi@0:             return c;
aoqi@0:     }
aoqi@0: }