/*
 * Copyright 2005-2006 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */
/*
 * $Id: SAAJMetaFactory.java,v 1.4 2006/03/30 00:59:39 ofung Exp $
 * $Revision: 1.4 $
 * $Date: 2006/03/30 00:59:39 $
 */


package javax.xml.soap;

/**
* The access point for the implementation classes of the factories defined in the
* SAAJ API. All of the <code>newInstance</code> methods defined on factories in 
* SAAJ 1.3 defer to instances of this class to do the actual object creation. 
* The implementations of <code>newInstance()</code> methods (in SOAPFactory and MessageFactory)
* that existed in SAAJ 1.2 have been updated to also delegate to the SAAJMetaFactory when the SAAJ 1.2
* defined lookup fails to locate the Factory implementation class name. 
* 
* <p>
* SAAJMetaFactory is a service provider interface. There are no public methods on this
* class.
*
* @author SAAJ RI Development Team
* @since SAAJ 1.3
*/

public abstract class SAAJMetaFactory {
    static private final String META_FACTORY_CLASS_PROPERTY =
        "javax.xml.soap.MetaFactory";
    static private final String DEFAULT_META_FACTORY_CLASS =
        "com.sun.xml.internal.messaging.saaj.soap.SAAJMetaFactoryImpl";

    /**
     * Creates a new instance of a concrete <code>SAAJMetaFactory</code> object. 
     * The SAAJMetaFactory is an SPI, it pulls the creation of the other factories together into a 
     * single place. Changing out the SAAJMetaFactory has the effect of changing out the entire SAAJ 
     * implementation. Service providers provide the name of their <code>SAAJMetaFactory</code>
     * implementation. 
     *
     * This method uses the following ordered lookup procedure to determine the SAAJMetaFactory implementation class to load:
     * <UL>
     *  <LI> Use the javax.xml.soap.MetaFactory system property.
     *  <LI> Use the properties file "lib/jaxm.properties" in the JRE directory. This configuration file is in standard 
     * java.util.Properties format and contains the fully qualified name of the implementation class with the key being the 
     * system property defined above. 
     *  <LI> Use the Services API (as detailed in the JAR specification), if available, to determine the classname. The Services API 
     * will look for a classname in the file META-INF/services/javax.xml.soap.MetaFactory in jars available to the runtime.
     *  <LI> Default to com.sun.xml.internal.messaging.saaj.soap.SAAJMetaFactoryImpl.
     * </UL>
     *
     * @return a concrete <code>SAAJMetaFactory</code> object
     * @exception SOAPException if there is an error in creating the <code>SAAJMetaFactory</code>
     */
    static SAAJMetaFactory getInstance() throws SOAPException {
            try {
                SAAJMetaFactory instance =
                    (SAAJMetaFactory) FactoryFinder.find(
                        META_FACTORY_CLASS_PROPERTY,
                        DEFAULT_META_FACTORY_CLASS);
                return instance;
            } catch (Exception e) {
                throw new SOAPException(
                    "Unable to create SAAJ meta-factory" + e.getMessage());
            }
    }

    protected SAAJMetaFactory() { }

     /**
      * Creates a <code>MessageFactory</code> object for 
      * the given <code>String</code> protocol. 
      *
      * @param protocol a <code>String</code> indicating the protocol
      * @exception SOAPException if there is an error in creating the
      *            MessageFactory
      * @see SOAPConstants#SOAP_1_1_PROTOCOL
      * @see SOAPConstants#SOAP_1_2_PROTOCOL
      * @see SOAPConstants#DYNAMIC_SOAP_PROTOCOL
      */
    protected abstract MessageFactory newMessageFactory(String protocol)
        throws SOAPException;

     /**
      * Creates a <code>SOAPFactory</code> object for 
      * the given <code>String</code> protocol. 
      *
      * @param protocol a <code>String</code> indicating the protocol
      * @exception SOAPException if there is an error in creating the
      *            SOAPFactory
      * @see SOAPConstants#SOAP_1_1_PROTOCOL
      * @see SOAPConstants#SOAP_1_2_PROTOCOL
      * @see SOAPConstants#DYNAMIC_SOAP_PROTOCOL
      */
    protected abstract SOAPFactory newSOAPFactory(String protocol)
        throws SOAPException;
}
