/*
 * 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;

The context in which a piece of Message content is contained.  A
MessageContext object is returned by the
getMessageContext method of the
MessageAware interface.  MessageAware is
typically implemented by DataSources to allow a
DataContentHandler to pass on information about the
context in which a data content object is operating.
See Also:
MessageAware
DataSource
DataContentHandler
Since:
	JavaMail 1.1/**
 * The context in which a piece of Message content is contained.  A
 * <code>MessageContext</code> object is returned by the
 * <code>getMessageContext</code> method of the
 * <code>MessageAware</code> interface.  <code>MessageAware</code> is
 * typically implemented by <code>DataSources</code> to allow a
 * <code>DataContentHandler</code> to pass on information about the
 * context in which a data content object is operating.
 *
 * @see javax.mail.MessageAware
 * @see javax.activation.DataSource
 * @see javax.activation.DataContentHandler
 * @since	JavaMail 1.1
 */
public class MessageContext {
    private Part part;

    
Create a MessageContext object describing the context of the given Part.
Params:
part – 	the Part/**
     * Create a MessageContext object describing the context of the given Part.
     *
     * @param	part	the Part
     */
    public MessageContext(Part part) {
	this.part = part;
    }

    
Return the Part that contains the content.
Returns:
	the containing Part, or null if not known/**
     * Return the Part that contains the content.
     *
     * @return	the containing Part, or null if not known
     */
    public Part getPart() {
	return part;
    }

    
Return the Message that contains the content.
Follows the parent chain up through containing Multipart
objects until it comes to a Message object, or null.
Returns:
	the containing Message, or null if not known/**
     * Return the Message that contains the content.
     * Follows the parent chain up through containing Multipart
     * objects until it comes to a Message object, or null.
     *
     * @return	the containing Message, or null if not known
     */
    public Message getMessage() {
	try {
	    return getMessage(part);
	} catch (MessagingException ex) {
	    return null;
	}
    }

    
Return the Message containing an arbitrary Part.
Follows the parent chain up through containing Multipart
objects until it comes to a Message object, or null.
See Also:
BodyPart.getParent
Multipart.getParent
Returns:
	the containing Message, or null if none/**
     * Return the Message containing an arbitrary Part.
     * Follows the parent chain up through containing Multipart
     * objects until it comes to a Message object, or null.
     *
     * @return	the containing Message, or null if none
     * @see javax.mail.BodyPart#getParent
     * @see javax.mail.Multipart#getParent
     */
    private static Message getMessage(Part p) throws MessagingException {
	while (p != null) {
	    if (p instanceof Message)
		return (Message)p;
	    BodyPart bp = (BodyPart)p;
	    Multipart mp = bp.getParent();
	    if (mp == null)	// MimeBodyPart might not be in a MimeMultipart
		return null;
	    p = mp.getParent();
	}
	return null;
    }

    
Return the Session we're operating in.
Returns:
	the Session, or null if not known/**
     * Return the Session we're operating in.
     *
     * @return	the Session, or null if not known
     */
    public Session getSession() {
	Message msg = getMessage();
	return msg != null ? msg.getSession() : null;
    }
}