/*
 * Copyright 2004,2005 The Apache Software Foundation.
 * Copyright 2006 International Business Machines Corp.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.axis2.jaxws.message.factory;

import javax.xml.namespace.QName;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;

import org.apache.axiom.om.OMElement;
import org.apache.axis2.jaxws.message.Block;
import org.apache.axis2.jaxws.message.MessageException;

/**
 * BlockFactory
 * 
 * Interface to create Block objects
 * An object is created from either a reader, another Block or the BusinessObject.
 * Some business objects (like JAXB) have an associated context object (JAXBContext),
 * these are also passed to the createMethods.
 * 
 * The implementation of BlockFactories should always be singleton objects and
 * never carry any instance data.
 * 
 * The FactoryRegistry should be used to get access to a Factory
 * @see org.apache.axis2.jaxws.registry.FactoryRegistry
 */
public interface BlockFactory {

	/**
	 * createBlock from XMLStreamReader
	 * @param reader XMLStreamReader
	 * @param context Associated Context or null
	 * @param QName if known...if null the Block will determine the QName
	 * @throws XMLStreamException
	 */
	public Block createFrom(XMLStreamReader reader, Object context, QName qName) throws XMLStreamException;
	
	/**
	 * createBlock from XMLStreamReader
	 * @param omElement OMElement
	 * @param context Associated Context or null
	 * @param QName if known...if null the Block will determine the QName
	 * @throws XMLStreamException
	 */
	public Block createFrom(OMElement omElement, Object context, QName qName) throws XMLStreamException;
	
	/**
	 * createBlock from another Block
	 * If the other Block was created with the same factory and has the same context,
	 * the other Block is returned.
	 * If the other Block was created by a different factory or diffent context,
	 * a new block is returned (and the other block is consumed)
	 * @param other Block
	 * @param context Associated Context or null
	 * @throws XMLStreamException
	 */
	public Block createFrom(Block other, Object context) throws XMLStreamException, MessageException;
	
	/**
	 * Create from business object
	 * @param businessObject
	 * @param context Associated Context or null
	 * @param QName if known...if null the Block will determine the QName
	 */
	public Block createFrom(Object businessObject, Object context, QName qName) throws MessageException;
}