| /* |
| * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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| */ |
| |
| package com.sun.xml.internal.org.jvnet.mimepull; |
| |
| import java.io.*; |
| |
| |
| /** |
| * This is a utility class that provides various MIME related |
| * functionality. <p> |
| * |
| * There are a set of methods to encode and decode MIME headers as |
| * per RFC 2047. Note that, in general, these methods are |
| * <strong>not</strong> needed when using methods such as |
| * <code>setSubject</code> and <code>setRecipients</code>; JavaMail |
| * will automatically encode and decode data when using these "higher |
| * level" methods. The methods below are only needed when maniuplating |
| * raw MIME headers using <code>setHeader</code> and <code>getHeader</code> |
| * methods. A brief description on handling such headers is given below: <p> |
| * |
| * RFC 822 mail headers <strong>must</strong> contain only US-ASCII |
| * characters. Headers that contain non US-ASCII characters must be |
| * encoded so that they contain only US-ASCII characters. Basically, |
| * this process involves using either BASE64 or QP to encode certain |
| * characters. RFC 2047 describes this in detail. <p> |
| * |
| * In Java, Strings contain (16 bit) Unicode characters. ASCII is a |
| * subset of Unicode (and occupies the range 0 - 127). A String |
| * that contains only ASCII characters is already mail-safe. If the |
| * String contains non US-ASCII characters, it must be encoded. An |
| * additional complexity in this step is that since Unicode is not |
| * yet a widely used charset, one might want to first charset-encode |
| * the String into another charset and then do the transfer-encoding. |
| * <p> |
| * Note that to get the actual bytes of a mail-safe String (say, |
| * for sending over SMTP), one must do |
| * <p><blockquote><pre> |
| * |
| * byte[] bytes = string.getBytes("iso-8859-1"); |
| * |
| * </pre></blockquote><p> |
| * |
| * The <code>setHeader</code> and <code>addHeader</code> methods |
| * on MimeMessage and MimeBodyPart assume that the given header values |
| * are Unicode strings that contain only US-ASCII characters. Hence |
| * the callers of those methods must insure that the values they pass |
| * do not contain non US-ASCII characters. The methods in this class |
| * help do this. <p> |
| * |
| * The <code>getHeader</code> family of methods on MimeMessage and |
| * MimeBodyPart return the raw header value. These might be encoded |
| * as per RFC 2047, and if so, must be decoded into Unicode Strings. |
| * The methods in this class help to do this. <p> |
| * |
| * Several System properties control strict conformance to the MIME |
| * spec. Note that these are not session properties but must be set |
| * globally as System properties. <p> |
| * |
| * The <code>mail.mime.decodetext.strict</code> property controls |
| * decoding of MIME encoded words. The MIME spec requires that encoded |
| * words start at the beginning of a whitespace separated word. Some |
| * mailers incorrectly include encoded words in the middle of a word. |
| * If the <code>mail.mime.decodetext.strict</code> System property is |
| * set to <code>"false"</code>, an attempt will be made to decode these |
| * illegal encoded words. The default is true. <p> |
| * |
| * The <code>mail.mime.encodeeol.strict</code> property controls the |
| * choice of Content-Transfer-Encoding for MIME parts that are not of |
| * type "text". Often such parts will contain textual data for which |
| * an encoding that allows normal end of line conventions is appropriate. |
| * In rare cases, such a part will appear to contain entirely textual |
| * data, but will require an encoding that preserves CR and LF characters |
| * without change. If the <code>mail.mime.encodeeol.strict</code> |
| * System property is set to <code>"true"</code>, such an encoding will |
| * be used when necessary. The default is false. <p> |
| * |
| * In addition, the <code>mail.mime.charset</code> System property can |
| * be used to specify the default MIME charset to use for encoded words |
| * and text parts that don't otherwise specify a charset. Normally, the |
| * default MIME charset is derived from the default Java charset, as |
| * specified in the <code>file.encoding</code> System property. Most |
| * applications will have no need to explicitly set the default MIME |
| * charset. In cases where the default MIME charset to be used for |
| * mail messages is different than the charset used for files stored on |
| * the system, this property should be set. <p> |
| * |
| * The current implementation also supports the following System property. |
| * <p> |
| * The <code>mail.mime.ignoreunknownencoding</code> property controls |
| * whether unknown values in the <code>Content-Transfer-Encoding</code> |
| * header, as passed to the <code>decode</code> method, cause an exception. |
| * If set to <code>"true"</code>, unknown values are ignored and 8bit |
| * encoding is assumed. Otherwise, unknown values cause a MessagingException |
| * to be thrown. |
| * |
| * @author John Mani |
| * @author Bill Shannon |
| */ |
| |
| /* FROM mail.jar */ |
| final class MimeUtility { |
| |
| // This class cannot be instantiated |
| private MimeUtility() { } |
| |
| private static final boolean ignoreUnknownEncoding = |
| PropUtil.getBooleanSystemProperty( |
| "mail.mime.ignoreunknownencoding", false); |
| |
| /** |
| * Decode the given input stream. The Input stream returned is |
| * the decoded input stream. All the encodings defined in RFC 2045 |
| * are supported here. They include "base64", "quoted-printable", |
| * "7bit", "8bit", and "binary". In addition, "uuencode" is also |
| * supported. <p> |
| * |
| * In the current implementation, if the |
| * <code>mail.mime.ignoreunknownencoding</code> system property is set to |
| * <code>"true"</code>, unknown encoding values are ignored and the |
| * original InputStream is returned. |
| * |
| * @param is input stream |
| * @param encoding the encoding of the stream. |
| * @return decoded input stream. |
| * @exception MessagingException if the encoding is unknown |
| */ |
| public static InputStream decode(InputStream is, String encoding) |
| throws DecodingException { |
| if (encoding.equalsIgnoreCase("base64")) |
| return new BASE64DecoderStream(is); |
| else if (encoding.equalsIgnoreCase("quoted-printable")) |
| return new QPDecoderStream(is); |
| else if (encoding.equalsIgnoreCase("uuencode") || |
| encoding.equalsIgnoreCase("x-uuencode") || |
| encoding.equalsIgnoreCase("x-uue")) |
| return new UUDecoderStream(is); |
| else if (encoding.equalsIgnoreCase("binary") || |
| encoding.equalsIgnoreCase("7bit") || |
| encoding.equalsIgnoreCase("8bit")) |
| return is; |
| else { |
| if (!ignoreUnknownEncoding) { |
| throw new DecodingException("Unknown encoding: " + encoding); |
| } |
| return is; |
| } |
| } |
| } |