Java tutorial
/* * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. * * Copyright (c) 1997-2017 Oracle and/or its affiliates. All rights reserved. * * The contents of this file are subject to the terms of either the GNU * General Public License Version 2 only ("GPL") or the Common Development * and Distribution License("CDDL") (collectively, the "License"). You * may not use this file except in compliance with the License. You can * obtain a copy of the License at * https://oss.oracle.com/licenses/CDDL+GPL-1.1 * or LICENSE.txt. See the License for the specific * language governing permissions and limitations under the License. * * When distributing the software, include this License Header Notice in each * file and include the License file at LICENSE.txt. * * GPL Classpath Exception: * Oracle designates this particular file as subject to the "Classpath" * exception as provided by Oracle in the GPL Version 2 section of the License * file that accompanied this code. * * Modifications: * If applicable, add the following below the License Header, with the fields * enclosed by brackets [] replaced by your own identifying information: * "Portions Copyright [year] [name of copyright owner]" * * Contributor(s): * If you wish your version of this file to be governed by only the CDDL or * only the GPL Version 2, indicate your decision by adding "[Contributor] * elects to include this software in this distribution under the [CDDL or GPL * Version 2] license." If you don't indicate a single choice of license, a * recipient has the option to distribute your version of this file under * either the CDDL, the GPL Version 2 or to extend the choice of license to * its licensees as provided above. However, if you add GPL Version 2 code * and therefore, elected the GPL Version 2 license, then the option applies * only if the new code is made subject to such option by the copyright * holder. */ package javax.mail.internet; import java.io.*; import java.util.Enumeration; import javax.mail.*; import com.sun.mail.util.LineOutputStream; /** * A MimeBodyPart that handles data that has already been encoded. * This class is useful when constructing a message and attaching * data that has already been encoded (for example, using base64 * encoding). The data may have been encoded by the application, * or may have been stored in a file or database in encoded form. * The encoding is supplied when this object is created. The data * is attached to this object in the usual fashion, by using the * <code>setText</code>, <code>setContent</code>, or * <code>setDataHandler</code> methods. * * @since JavaMail 1.4 */ public class PreencodedMimeBodyPart extends MimeBodyPart { private String encoding; /** * Create a PreencodedMimeBodyPart that assumes the data is * encoded using the specified encoding. The encoding must * be a MIME supported Content-Transfer-Encoding. * * @param encoding the Content-Transfer-Encoding */ public PreencodedMimeBodyPart(String encoding) { this.encoding = encoding; } /** * Returns the content transfer encoding specified when * this object was created. */ @Override public String getEncoding() throws MessagingException { return encoding; } /** * Output the body part as an RFC 822 format stream. * * @exception IOException if an error occurs writing to the * stream or if an error is generated * by the javax.activation layer. * @exception MessagingException for other failures * @see javax.activation.DataHandler#writeTo */ @Override public void writeTo(OutputStream os) throws IOException, MessagingException { // see if we already have a LOS LineOutputStream los = null; if (os instanceof LineOutputStream) { los = (LineOutputStream) os; } else { los = new LineOutputStream(os); } // First, write out the header Enumeration<String> hdrLines = getAllHeaderLines(); while (hdrLines.hasMoreElements()) los.writeln(hdrLines.nextElement()); // The CRLF separator between header and content los.writeln(); // Finally, the content, already encoded. getDataHandler().writeTo(os); os.flush(); } /** * Force the <code>Content-Transfer-Encoding</code> header to use * the encoding that was specified when this object was created. */ @Override protected void updateHeaders() throws MessagingException { super.updateHeaders(); MimeBodyPart.setEncoding(this, encoding); } }