# XMLEventWriterDelegate.java

    /**
     *  Copyright (c) 2005-2010, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
     *
     *  WSO2 Inc. licenses this file to you 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.synapse.commons.json;

    import org.apache.synapse.commons.staxon.core.event.SimpleXMLEventWriter;

    import javax.xml.namespace.QName;
    import javax.xml.stream.XMLStreamConstants;
    import javax.xml.stream.XMLStreamException;
    import javax.xml.stream.XMLStreamWriter;
    import javax.xml.stream.events.Attribute;
    import javax.xml.stream.events.Characters;
    import javax.xml.stream.events.Comment;
    import javax.xml.stream.events.DTD;
    import javax.xml.stream.events.EntityReference;
    import javax.xml.stream.events.Namespace;
    import javax.xml.stream.events.ProcessingInstruction;
    import javax.xml.stream.events.StartDocument;
    import javax.xml.stream.events.StartElement;
    import javax.xml.stream.events.XMLEvent;
    import java.util.Iterator;

    final class XMLEventWriterDelegate extends SimpleXMLEventWriter {
        private XMLStreamWriter delegate;

        public XMLEventWriterDelegate(XMLStreamWriter delegate) {
            super(delegate);
            this.delegate = delegate;
        }

        public void add(XMLEvent event) throws XMLStreamException {
            switch (event.getEventType()) {
                case XMLStreamConstants.ATTRIBUTE:
                    Attribute attribute = (Attribute) event;
                    QName attrName = attribute.getName();
                    delegate.writeAttribute(attrName.getPrefix(),
                            attrName.getNamespaceURI(),
                            attrName.getLocalPart(), attribute.getValue());
                    break;
                case XMLStreamConstants.END_DOCUMENT:
                    delegate.writeEndDocument();
                    break;
                case XMLStreamConstants.END_ELEMENT:
                    delegate.writeEndElement();
                    break;
                case XMLStreamConstants.NAMESPACE:
                    Namespace namespace = (Namespace) event;
                    delegate.writeNamespace(namespace.getPrefix(), namespace.getNamespaceURI());
                    break;
                case XMLStreamConstants.START_DOCUMENT:
                    StartDocument startDocument = (StartDocument) event;
                    if (startDocument.encodingSet()) { // encoding defined?
                        delegate.writeStartDocument(startDocument.getCharacterEncodingScheme(), startDocument.getVersion());
                    } else {
                        delegate.writeStartDocument(startDocument.getVersion());
                    }
                    break;
                case XMLStreamConstants.START_ELEMENT:
                    StartElement startElement = event.asStartElement();
                    QName elemName = startElement.getName();
                    delegate.writeStartElement(elemName.getPrefix(), elemName.getLocalPart(), elemName.getNamespaceURI());
                    Iterator<?> namespaces = startElement.getNamespaces();
                    while (namespaces.hasNext()) {
                        add((Namespace) namespaces.next());
                    }
                    Iterator<?> attributes = startElement.getAttributes();
                    while (attributes.hasNext()) {
                        add((Attribute) attributes.next());
                    }
                    break;
                case XMLStreamConstants.CHARACTERS:
                case XMLStreamConstants.CDATA:
                    Characters characters = event.asCharacters();
                    if (characters.isCData()) {
                        delegate.writeCData(characters.getData());
                    } else {
                        delegate.writeCharacters(characters.getData());
                    }
                    break;
                case XMLStreamConstants.COMMENT:
                    delegate.writeComment(((Comment) event).getText());
                    break;
                case XMLStreamConstants.DTD:
                    delegate.writeDTD(((DTD) event).getDocumentTypeDeclaration());
                    break;
                case XMLStreamConstants.ENTITY_REFERENCE:
                    delegate.writeEntityRef(((EntityReference) event).getName());
                    break;
                case XMLStreamConstants.PROCESSING_INSTRUCTION:
                    ProcessingInstruction processingInstruction = (ProcessingInstruction) event;
                    delegate.writeProcessingInstruction(processingInstruction.getTarget(), processingInstruction.getData());
                    break;
                case XMLStreamConstants.SPACE:
                    break;
                default:
                    throw new XMLStreamException("Cannot write event " + event);
            }
        }

    }