JavaMail Source Code Files are provided in the source package file, httpcomponents-client-5.2-src.zip.

You can browse JavaMail Source Code files below:

⏎ com/sun/mail/handlers/multipart_mixed.java

/*
 * 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 com.sun.mail.handlers;

import java.io.*;
import javax.activation.*;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.internet.MimeMultipart;


public class multipart_mixed extends handler_base {
    private static ActivationDataFlavor[] myDF = {
	new ActivationDataFlavor(Multipart.class,
				    "multipart/mixed", "Multipart")
    };

    @Override
    protected ActivationDataFlavor[] getDataFlavors() {
	return myDF;
    }

    /**
     * Return the content.
     */
    @Override
    public Object getContent(DataSource ds) throws IOException {
	try {
	    return new MimeMultipart(ds); 
	} catch (MessagingException e) {
	    IOException ioex =
		new IOException("Exception while constructing MimeMultipart");
	    ioex.initCause(e);
	    throw ioex;
	}
    }
    
    /**
     * Write the object to the output stream, using the specific MIME type.
     */
    @Override
    public void writeTo(Object obj, String mimeType, OutputStream os) 
			throws IOException {
	if (obj instanceof Multipart) {
	    try {
		((Multipart)obj).writeTo(os);
	    } catch (MessagingException e) {
		IOException ioex =
		    new IOException("Exception writing Multipart");
		ioex.initCause(e);
		throw ioex;
	    }
	}
    }
}

⏎ com/sun/mail/handlers/multipart_mixed.java

Or download all of them as a single archive file:

File name: javax.mail-1.6.2-sources.jar
File size: 851487 bytes
Release date: 2018-08-29
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