# NashornJavaScriptXmlHelper.java

    /*
     * Copyright (c) 2017, 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.mediators.bsf;

    import org.apache.axiom.om.OMElement;
    import org.apache.axiom.om.OMException;
    import org.apache.axiom.om.util.AXIOMUtil;
    import org.apache.axis2.util.XMLUtils;
    import org.apache.bsf.xml.DefaultXMLHelper;
    import org.w3c.dom.Document;
    import org.w3c.dom.Element;

    import javax.script.ScriptException;
    import javax.xml.stream.XMLStreamException;

    /**
     * This class will provide the operations to convert between xml elements of scripts and OMElements.
     */
    public class NashornJavaScriptXmlHelper extends DefaultXMLHelper {

        /**
         * This method will convert the message payload in to xml.
         *
         * @param scriptXML from java script
         * @return XML content as OMElement
         * @throws ScriptException when error
         */
        public OMElement toOMElement(Object scriptXML) throws ScriptException {
            OMElement omElement;
            if (scriptXML == null) {
                return null;
            } else if (scriptXML instanceof String) {
                try {
                    String xmlString = scriptXML.toString();
                    omElement = AXIOMUtil.stringToOM(xmlString);

                } catch (XMLStreamException | OMException e) {
                    ScriptException scriptException = new ScriptException("Failed to create OMElement with provided " +
                            "payload");
                    scriptException.initCause(e);
                    throw scriptException;
                }
            } else if (scriptXML instanceof Document) {
                try {
                    Element element = ((Document) scriptXML).getDocumentElement();
                    omElement = XMLUtils.toOM(element);
                } catch (Exception e) {
                    ScriptException scriptException = new ScriptException("Failed to create OMElement with provided " +
                            "payload");
                    scriptException.initCause(e);
                    throw scriptException;
                }
            } else if (scriptXML instanceof OMElement) {
                omElement = (OMElement) scriptXML;
            } else {
                throw new ScriptException("Unsupported type provide for XML. type: " + scriptXML.getClass());
            }
            return omElement;
        }

        /**
         * This method will convert the message payload in to xml string.
         *
         * @param omElement axiom element representation of xml document
         * @return xml string by adding the xml content
         * @throws ScriptException when error
         */
        public Object toScriptXML(OMElement omElement) throws ScriptException {
            String xmlString;
            if (omElement == null) {
                return null;
            }
            try {
                xmlString = omElement.toStringWithConsume();
            } catch (XMLStreamException e) {
                ScriptException scriptException = new ScriptException("Failed to convert OMElement to a string");
                scriptException.initCause(e);
                throw scriptException;
            }
            return xmlString;
        }
    }