/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 2005-2011 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://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/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 packager/legal/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.xml.bind.attachment;

import javax.activation.DataHandler;
import javax.xml.bind.Marshaller;

/**
 * <p>Enable JAXB marshalling to optimize storage of binary data.</p>
 * 
 * <p>This API enables an efficient cooperative creation of optimized
 * binary data formats between a JAXB marshalling process and a MIME-based package
 * processor. A JAXB implementation marshals the root body of a MIME-based package, 
 * delegating the creation of referenceable MIME parts to 
 * the MIME-based package processor that implements this abstraction.</p>
 *
 * <p>XOP processing is enabled when {@link #isXOPPackage()} is true.
 *    See {@link #addMtomAttachment(DataHandler, String, String)} for details.
 * </p>
 * 
 * <p>WS-I Attachment Profile 1.0 is supported by 
 * {@link #addSwaRefAttachment(DataHandler)} being called by the 
 * marshaller for each JAXB property related to 
 * {http://ws-i.org/profiles/basic/1.1/xsd}swaRef.</p>
 * 
 *
 * @author Marc Hadley
 * @author Kohsuke Kawaguchi
 * @author Joseph Fialli
 * @since JAXB 2.0
 * 
 * @see Marshaller#setAttachmentMarshaller(AttachmentMarshaller)
 * 
 * @see <a href="http://www.w3.org/TR/2005/REC-xop10-20050125/">XML-binary Optimized Packaging</a>
 * @see <a href="http://www.ws-i.org/Profiles/AttachmentsProfile-1.0-2004-08-24.html">WS-I Attachments Profile Version 1.0.</a>
 */
public abstract class AttachmentMarshaller {

    /**
     * <p>Consider MIME content <code>data</code> for optimized binary storage as an attachment.
     *
     * <p>
     * This method is called by JAXB marshal process when {@link #isXOPPackage()} is 
     * <code>true</code>, for each element whose datatype is "base64Binary", as described in 
     * Step 3 in 
     * <a href="http://www.w3.org/TR/2005/REC-xop10-20050125/#creating_xop_packages">Creating XOP Packages</a>. 
     *
     * <p>
     * The method implementor determines whether <code>data</code> shall be attached separately 
     * or inlined as base64Binary data. If the implementation chooses to optimize the storage 
     * of the binary data as a MIME part, it is responsible for attaching <code>data</code> to the 
     * MIME-based package, and then assigning an unique content-id, cid, that identifies
     * the MIME part within the MIME message. This method returns the cid, 
     * which enables the JAXB marshaller to marshal a XOP element that refers to that cid in place
     * of marshalling the binary data. When the method returns null, the JAXB marshaller
     * inlines <code>data</code> as base64binary data.
     *
     * <p>
     * The caller of this method is required to meet the following constraint.
     * If the element infoset item containing <code>data</code> has the attribute 
     * <code>xmime:contentType</code> or if the JAXB property/field representing 
     * <code>data</code>is annotated with a known MIME type, 
     * <code>data.getContentType()</code> should be set to that MIME type.
     *
     * <p>
     * The <code>elementNamespace</code> and <code>elementLocalName</code>
     * parameters provide the
     * context that contains the binary data. This information could
     * be used by the MIME-based package processor to determine if the
     * binary data should be inlined or optimized as an attachment.
     *
     * @param data
     *       represents the data to be attached. Must be non-null.
     * @param elementNamespace
     *      the namespace URI of the element that encloses the base64Binary data.
     *      Can be empty but never null. 
     * @param elementLocalName
     *      The local name of the element. Always a non-null valid string.
     *        
     * @return
     *     a valid content-id URI (see <a href="http://www.w3.org/TR/xop10/#RFC2387">RFC 2387</a>) that identifies the attachment containing <code>data</code>.     
     *     Otherwise, null if the attachment was not added and should instead be inlined in the message.
     *  
     * @see <a href="http://www.w3.org/TR/2005/REC-xop10-20050125/">XML-binary Optimized Packaging</a>
     * @see <a href="http://www.w3.org/TR/xml-media-types/">Describing Media Content of Binary Data in XML</a>
     */
    public abstract String addMtomAttachment(DataHandler data, String elementNamespace, String elementLocalName);

    /**
     * <p>Consider binary <code>data</code> for optimized binary storage as an attachment.
     *
     * <p>Since content type is not known, the attachment's MIME content type must be set to "application/octet-stream".</p>
     *
     * <p>
     * The <code>elementNamespace</code> and <code>elementLocalName</code>
     * parameters provide the
     * context that contains the binary data. This information could
     * be used by the MIME-based package processor to determine if the
     * binary data should be inlined or optimized as an attachment.
     *
     * @param data
     *      represents the data to be attached. Must be non-null. The actual data region is
     *      specified by <tt>(data,offset,length)</tt> tuple.
     *
     * @param offset
     *       The offset within the array of the first byte to be read; 
     *       must be non-negative and no larger than array.length
     * 
     * @param length
     *       The number of bytes to be read from the given array; 
     *       must be non-negative and no larger than array.length
     *
     * @param mimeType
     *      If the data has an associated MIME type known to JAXB, that is passed
     *      as this parameter. If none is known, "application/octet-stream".
     *      This parameter may never be null.
     * 
     * @param elementNamespace
     *      the namespace URI of the element that encloses the base64Binary data.
     *      Can be empty but never null.
     * 
     * @param elementLocalName
     *      The local name of the element. Always a non-null valid string.
     * 
     * @return content-id URI, cid, to the attachment containing  
     *         <code>data</code> or null if data should be inlined.
     *
     * @see #addMtomAttachment(DataHandler, String, String)
     */
    public abstract String addMtomAttachment(byte[] data, int offset, int length, String mimeType, String elementNamespace, String elementLocalName);

    /**
     * <p>Read-only property that returns true if JAXB marshaller should enable XOP creation.</p>
     *
     * <p>This value must not change during the marshalling process. When this
     * value is true, the <code>addMtomAttachment(...)</code> method
     * is invoked when the appropriate binary datatypes are encountered by
     * the marshal process.</p>
     *
     * <p>Marshaller.marshal() must throw IllegalStateException if this value is <code>true</code> 
     * and the XML content to be marshalled violates Step 1 in 
     * <a href="http://www.w3.org/TR/2005/REC-xop10-20050125/#creating_xop_packages">Creating XOP Pacakges</a>
     * http://www.w3.org/TR/2005/REC-xop10-20050125/#creating_xop_packages. 
     * <i>"Ensure the Original XML Infoset contains no element information item with a 
     * [namespace name] of "http://www.w3.org/2004/08/xop/include" and a [local name] of Include"</i>
     *
     * <p>When this method returns true and during the marshal process
     * at least one call to <code>addMtomAttachment(...)</code> returns 
     * a content-id, the MIME-based package processor must label the
     * root part with the application/xop+xml media type as described in 
     * Step 5 of
     * <a href="http://www.w3.org/TR/2005/REC-xop10-20050125/#creating_xop_packages">Creating XOP Pacakges</a>.<p>
     *
     * @return true when MIME context is a XOP Package.
     */
    public boolean isXOPPackage() { return false; }

   /**
    * <p>Add MIME <code>data</code> as an attachment and return attachment's content-id, cid.</p>
    * 
    * <p>
    * This method is called by JAXB marshal process for each element/attribute typed as 
    * {http://ws-i.org/profiles/basic/1.1/xsd}swaRef. The MIME-based package processor
    * implementing this method is responsible for attaching the specified data to a 
    * MIME attachment, and generating a content-id, cid, that uniquely identifies the attachment 
    * within the MIME-based package.
    *
    * <p>Caller inserts the returned content-id, cid, into the XML content being marshalled.</p>
    *
    * @param data
    *       represents the data to be attached. Must be non-null. 
    * @return
    *       must be a valid URI used as cid. Must satisfy Conformance Requirement R2928 from
    *       <a href="http://www.ws-i.org/Profiles/AttachmentsProfile-1.0-2004-08-24.html#Referencing_Attachments_from_the_SOAP_Envelope">WS-I Attachments Profile Version 1.0.</a>
    */
    public abstract String addSwaRefAttachment(DataHandler data);
}

