NamespaceContext2.java

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 2013 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 jaxb1.impl.runtime;

import javax.xml.namespace.NamespaceContext;

/**
 * Maintains namespace<->prefix bindings.
 * 
 * <p>
 * This interface extends {@link NamespaceContext} and provides
 * an additional functionality, which is necessary to declare
 * namespaced attributes on elements. The added method is for
 * self-consumption by the marshaller.
 * 
 * This object is composed into a Serializer.
 */
public interface NamespaceContext2 extends NamespaceContext
{
    /**
     * Declares a new namespace binding within the current context.
     * 
     * <p>
     * The prefix is automatically assigned by MarshallingContext. If
     * a given namespace URI is already declared, nothing happens.
     * 
     * <p>
     * It is <b>NOT</b> an error to declare the same namespace URI
     * more than once.
     * 
     * <p>
     * For marshalling to work correctly, all namespace bindings
     * for an element must be declared between its startElement method and
     * its endAttributes event. Calling the same method with the same
     * parameter between the endAttributes and the endElement returns
     * the same prefix.
     * 
     * @param   requirePrefix
     *      If this parameter is true, this method must assign a prefix
     *      to this namespace, even if it's already bound to the default
     *      namespace. IOW, this method will never return null if this
     *      flag is true. This functionality is necessary to declare
     *      namespace URI used for attribute names.
     * @param   preferedPrefix
     *      If the caller has any particular preference to the
     *      prefix, pass that as a parameter. The callee will try
     *      to honor it. Set null if there's no particular preference.
     * 
     * @return
     *      returns the assigned prefix. If the namespace is bound to
     *      the default namespace, null is returned.
     */
    String declareNamespace( String namespaceUri, String preferedPrefix, boolean requirePrefix );
}