# CommonScriptMessageContext.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.OMAttribute;
    import org.apache.axiom.om.OMElement;
    import org.apache.axiom.om.OMException;
    import org.apache.axiom.om.OMNode;
    import org.apache.axiom.soap.SOAPBody;
    import org.apache.axiom.soap.SOAPEnvelope;
    import org.apache.axiom.soap.SOAPFactory;
    import org.apache.axiom.soap.SOAPHeader;
    import org.apache.axiom.soap.SOAPHeaderBlock;
    import org.apache.axis2.AxisFault;
    import org.apache.axis2.addressing.EndpointReference;
    import org.apache.axis2.addressing.RelatesTo;
    import org.apache.axis2.context.OperationContext;
    import org.apache.bsf.xml.XMLHelper;
    import org.apache.commons.io.output.ByteArrayOutputStream;
    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;
    import org.apache.http.protocol.HTTP;
    import org.apache.synapse.ContinuationState;
    import org.apache.synapse.FaultHandler;
    import org.apache.synapse.Mediator;
    import org.apache.synapse.MessageContext;
    import org.apache.synapse.SynapseConstants;
    import org.apache.synapse.commons.json.JsonUtil;
    import org.apache.synapse.config.SynapseConfiguration;
    import org.apache.synapse.config.xml.XMLConfigConstants;
    import org.apache.synapse.core.SynapseEnvironment;
    import org.apache.synapse.core.axis2.Axis2MessageContext;
    import org.apache.synapse.endpoints.Endpoint;
    import org.mozilla.javascript.ConsString;
    import org.mozilla.javascript.NativeArray;
    import org.mozilla.javascript.NativeObject;
    import org.mozilla.javascript.Wrapper;
    import org.mozilla.javascript.xml.XMLObject;

    import java.io.IOException;
    import java.io.OutputStream;
    import java.io.StringWriter;

    import java.math.BigDecimal;
    import java.math.BigInteger;
    import java.util.HashMap;
    import java.util.Iterator;
    import java.util.Map;
    import java.util.Set;
    import java.util.Stack;
    import javax.script.ScriptEngine;
    import javax.script.ScriptException;

    /**
     * CommonScriptMessageContext decorates the Synapse MessageContext adding methods to use the
     * message payload XML in a way natural to the scripting languages.
     */
    @SuppressWarnings({"UnusedDeclaration"})
    public class CommonScriptMessageContext implements ScriptMessageContext {
        private static final Log logger = LogFactory.getLog(CommonScriptMessageContext.class.getName());

        private static final String JSON_OBJECT = "JSON_OBJECT";
        private static final String JSON_TEXT = "JSON_TEXT";

        /** The actual Synapse message context reference. */
        private final MessageContext mc;

        /** The OMElement to scripting language object converter for the selected language. */
        private final XMLHelper xmlHelper;

        /** To keep Script Engine instance. */
        private ScriptEngine scriptEngine;

        public CommonScriptMessageContext(MessageContext mc, XMLHelper xmlHelper) {
            this.mc = mc;
            this.xmlHelper = xmlHelper;
        }

        /**
         * Get the XML representation of SOAP Body payload.
         * The payload is the first element inside the SOAP <Body> tags
         *
         * @return the XML SOAP Body
         * @throws ScriptException in-case of an error in getting
         * the XML representation of SOAP Body payload
         */
        @Override
        public Object getPayloadXML() throws ScriptException {
            return xmlHelper.toScriptXML(mc.getEnvelope().getBody().getFirstElement());
        }

        /**
         * Set the SOAP body payload from XML.
         *
         * @param payload Message payload
         * @throws ScriptException For errors in converting xml To OM
         * @throws OMException For errors in OM manipulation
         */
        @Override
        public void setPayloadXML(Object payload) throws OMException, ScriptException {
            SOAPBody body = mc.getEnvelope().getBody();
            OMElement firstChild = body.getFirstElement();
            OMElement omElement = xmlHelper.toOMElement(payload);
            if (firstChild == null) {
                body.addChild(omElement);
            } else {
                firstChild.insertSiblingAfter(omElement);
                firstChild.detach();
            }
        }

        /**
         * Get the JSON object representation of the JSON message body of the request.
         *
         * @return JSON object of the message body
         */
        @Override
        public Object getPayloadJSON() {
            return jsonObject(mc);
        }

        /**
         * Get the Message Payload as a text.
         *
         * @return Payload as text
         */
        @Override
        public Object getJsonText() {
            if (mc == null) {
                return "";
            }
            Object text = mc.getProperty(JSON_TEXT);
            return text == null ? "{}" : text;
        }

        /**
         * Get the Message Payload as a text.
         *
         * @return Payload as text
         */
        @Override
        public String getPayloadText() {
            if (JsonUtil.hasAJsonPayload(((Axis2MessageContext) mc).getAxis2MessageContext())) {
                return JsonUtil.jsonPayloadToString(((Axis2MessageContext) mc).getAxis2MessageContext());
            } else {
                return mc.getEnvelope().toString();
            }
        }

        /**
         * Saves the payload of this message context as a JSON payload.
         *
         * @param jsonPayload Javascript native object to be set as the message body
         * @throws ScriptException in case of creating a JSON object out of
         *                         the javascript native object.
         */
        public void setPayloadJSON0(Object jsonPayload) throws ScriptException {
            org.apache.axis2.context.MessageContext messageContext;
            messageContext = ((Axis2MessageContext) mc).getAxis2MessageContext();

            String jsonString;
            if (jsonPayload instanceof String) {
                jsonString = (String) jsonPayload;
            } else {
                jsonString = serializeJSON(jsonPayload);
            }
            try {
                JsonUtil.getNewJsonPayload(messageContext, jsonString, true, true);
            } catch (AxisFault axisFault) {
                throw new ScriptException(axisFault);
            }
            Object jsonObject = scriptEngine.eval('(' + jsonString + ')');
            setJsonObject(mc, jsonObject);
        }

        /**
         * Saves the JavaScript Object to the message context.
         *
         * @param messageContext The message context of the sequence
         * @param jsonObject JavaScript Object saved in this message context
         * @return true
         */
        @Override
        public boolean setJsonObject(MessageContext messageContext, Object jsonObject) {
            messageContext.setProperty(JSON_OBJECT, jsonObject);
            return true;
        }

        /**
         * Saves the JSON String to the message context.
         *
         * @param messageContext The message context of the sequence
         * @param jsonObject JavaScript Object saved in this message context
         * @return false if messageContext is null return true otherwise
         */
        @Override
        public boolean setJsonText(MessageContext messageContext, Object jsonObject) {
            if (messageContext == null) {
                return false;
            }
            messageContext.setProperty(JSON_TEXT, jsonObject);
            return true;
        }

        /**
         * Returns the JavaScript Object saved in this message context.
         *
         * @param messageContext The message context of the sequence
         * @return o JavaScript Object saved in this message context
         */
        @Override
        public Object jsonObject(MessageContext messageContext) {
            if (messageContext == null) {
                return null;
            }
            Object o = messageContext.getProperty(JSON_OBJECT);
            if (o == null) {
                if (this.scriptEngine == null) {
                    logger.error("Cannot create empty JSON object. ScriptEngine instance not available.");
                    return null;
                }
                try {
                    return this.scriptEngine.eval("({})");
                } catch (ScriptException e) {
                    logger.error("Could not return an empty JSON object. ", e);
                }
            }
            return o;
        }

        /**
         * Set a script engine.
         *
         * @param scriptEngine a ScriptEngine instance
         */
        @Override
        public void setScriptEngine(ScriptEngine scriptEngine) {
            this.scriptEngine = scriptEngine;
        }

        /**
         * Add a new SOAP header to the message.
         *
         * @param mustUnderstand the value for the <code>soapenv:mustUnderstand</code> attribute
         * @param content the XML for the new header
         * @throws ScriptException if an error occurs when converting the XML to OM
         */
        @Override
        public void addHeader(boolean mustUnderstand, Object content) throws ScriptException {
            SOAPEnvelope envelope = mc.getEnvelope();
            SOAPFactory factory = (SOAPFactory) envelope.getOMFactory();
            SOAPHeader header = envelope.getHeader();
            if (header == null) {
                header = factory.createSOAPHeader(envelope);
            }
            OMElement element = xmlHelper.toOMElement(content);
            // We can't add the element directly to the SOAPHeader. Instead, we need to copy the
            // information over to a SOAPHeaderBlock.
            SOAPHeaderBlock headerBlock = header.addHeaderBlock(element.getLocalName(),
                    element.getNamespace());
            for (Iterator it = element.getAllAttributes(); it.hasNext(); ) {
                headerBlock.addAttribute((OMAttribute) it.next());
            }
            headerBlock.setMustUnderstand(mustUnderstand);
            OMNode child = element.getFirstOMChild();
            while (child != null) {
                // Get the next child before addChild will detach the node from its original place.
                OMNode next = child.getNextOMSibling();
                headerBlock.addChild(child);
                child = next;
            }
        }

        /**
         * Get the XML representation of the complete SOAP envelope.
         *
         * @return return an object that represents the payload in the current scripting language
         * @throws ScriptException in-case of an error in getting
         * the XML representation of SOAP envelope
         */
        @Override
        public Object getEnvelopeXML() throws ScriptException {
            return xmlHelper.toScriptXML(mc.getEnvelope());
        }

        /**
         * This is used to set the value which specifies the receiver of the message.
         *
         * @param reference specifies the receiver of the message
         */
        @Override
        public void setTo(String reference) {
            mc.setTo(new EndpointReference(reference));
        }

        /**
         * This is used to set the value which specifies the receiver of the faults relating to the message.
         *
         * @param reference specifies the receiver of the faults relating to the message
         */
        @Override
        public void setFaultTo(String reference) {
            mc.setFaultTo(new EndpointReference(reference));
        }

        /**
         * This is used to set the value which specifies the sender of the message.
         *
         * @param reference specifies the sender of the message
         */
        @Override
        public void setFrom(String reference) {
            mc.setFrom(new EndpointReference(reference));
        }

        /**
         * This is used to set the value which specifies the receiver of the replies to the message.
         *
         * @param reference specifies the receiver of the replies to the message
         */
        @Override
        public void setReplyTo(String reference) {
            mc.setReplyTo(new EndpointReference(reference));
        }

        /**
         * {@inheritDoc}
         */
        public SynapseConfiguration getConfiguration() {
            return mc.getConfiguration();
        }

        /**
         * {@inheritDoc}
         */
        public void setConfiguration(SynapseConfiguration cfg) {
            mc.setConfiguration(cfg);
        }

        /**
         * {@inheritDoc}
         */
        public SynapseEnvironment getEnvironment() {
            return mc.getEnvironment();
        }

        /**
         * {@inheritDoc}
         */
        public void setEnvironment(SynapseEnvironment se) {
            mc.setEnvironment(se);
        }

        /**
         * {@inheritDoc}
         */
        public Map<String, Object> getContextEntries() {
            return mc.getContextEntries();
        }

        /**
         * {@inheritDoc}
         */
        public void setContextEntries(Map<String, Object> entries) {
            mc.setContextEntries(entries);
        }

        /**
         * {@inheritDoc}
         */
        public Object getProperty(String key) {
            return mc.getProperty(key);
        }

        /**
         * {@inheritDoc}
         */
        public Object getEntry(String key) {
            return mc.getEntry(key);
        }

        /**
         * {@inheritDoc}
         */
        public Object getLocalEntry(String key) {
            return mc.getLocalEntry(key);
        }

        /**
         * Add a new property to the message.
         *
         * @param key unique identifier of property
         * @param value value of property
         */
        public void setProperty(String key, Object value) {
            if (value instanceof XMLObject) {
                OMElement omElement = null;
                try {
                    omElement = xmlHelper.toOMElement(value);
                } catch (ScriptException e) {
                    mc.setProperty(key, value);
                }
                if (omElement != null) {
                    mc.setProperty(key, omElement);
                }
            } else {
                mc.setProperty(key, value);
            }
        }

        /**
         * Add a new property to the message.
         *
         * @param key unique identifier of property
         * @param value value of property
         * @param scope scope of the property
         */
        @Override
        public void setProperty(String key, Object value, String scope) {
            if (scope == null || XMLConfigConstants.SCOPE_DEFAULT.equals(scope)) {
                setProperty(key, value);
            } else if (XMLConfigConstants.SCOPE_AXIS2.equals(scope)) {
                //Setting property into the  Axis2 Message Context
                Axis2MessageContext axis2smc = (Axis2MessageContext) mc;
                org.apache.axis2.context.MessageContext axis2MessageCtx = axis2smc.getAxis2MessageContext();
                axis2MessageCtx.setProperty(key, value);
                handleSpecialProperties(key, value, axis2MessageCtx);

            } else if (XMLConfigConstants.SCOPE_TRANSPORT.equals(scope)) {
                //Setting Transport Headers
                Axis2MessageContext axis2smc = (Axis2MessageContext) mc;
                org.apache.axis2.context.MessageContext axis2MessageCtx = axis2smc.getAxis2MessageContext();
                Object headers = axis2MessageCtx.getProperty(org.apache.axis2.context.MessageContext.TRANSPORT_HEADERS);

                if (headers != null && headers instanceof Map) {
                    Map headersMap = (Map) headers;
                    headersMap.put(key, value);
                }
                if (headers == null) {
                    Map headersMap = new HashMap();
                    headersMap.put(key, value);
                    axis2MessageCtx.setProperty(org.apache.axis2.context.MessageContext.TRANSPORT_HEADERS, headersMap);
                }
            } else if (XMLConfigConstants.SCOPE_OPERATION.equals(scope)) {
                Axis2MessageContext axis2smc = (Axis2MessageContext) mc;
                org.apache.axis2.context.MessageContext axis2MessageCtx = axis2smc.getAxis2MessageContext();
                axis2smc.getAxis2MessageContext().getOperationContext().setProperty(key, value);
            }
        }

        /**
         * Remove property from the message.
         *
         * @param key unique identifier of property
         * @param scope scope of the property
         */
        @Override
        public void removeProperty(String key, String scope) {
            if (scope == null || XMLConfigConstants.SCOPE_DEFAULT.equals(scope)) {
                Set pros = mc.getPropertyKeySet();
                if (pros != null) {
                    pros.remove(key);
                }
            } else if (XMLConfigConstants.SCOPE_AXIS2.equals(scope)) {
                //Removing property from the Axis2 Message Context
                Axis2MessageContext axis2smc = (Axis2MessageContext) mc;
                org.apache.axis2.context.MessageContext axis2MessageCtx = axis2smc.getAxis2MessageContext();
                axis2MessageCtx.removeProperty(key);

            } else if (XMLConfigConstants.SCOPE_TRANSPORT.equals(scope)) {
                // Removing transport headers
                Axis2MessageContext axis2smc = (Axis2MessageContext) mc;
                org.apache.axis2.context.MessageContext axis2MessageCtx = axis2smc.getAxis2MessageContext();
                Object headers = axis2MessageCtx.getProperty(org.apache.axis2.context.MessageContext.TRANSPORT_HEADERS);
                if (headers != null && headers instanceof Map) {
                    Map headersMap = (Map) headers;
                    headersMap.remove(key);
                }
            } else if (XMLConfigConstants.SCOPE_OPERATION.equals(scope)) {
                // Removing operation scope headers
                Axis2MessageContext axis2smc = (Axis2MessageContext) mc;
                org.apache.axis2.context.MessageContext axis2MessageCtx = axis2smc.getAxis2MessageContext();
                OperationContext axis2oc = axis2MessageCtx.getOperationContext();
                axis2oc.removeProperty(key);
            }

        }

        /**
         * Add special properties such as content type to the message context.
         *
         * @param key unique identifier of property
         * @param value value of property
         * @param messageContext Axis2 message context
         */
        private void handleSpecialProperties(String key, Object value,
                org.apache.axis2.context.MessageContext messageContext) {
            if (org.apache.axis2.Constants.Configuration.MESSAGE_TYPE.equals(key)) {
                messageContext.setProperty(org.apache.axis2.Constants.Configuration.CONTENT_TYPE, value);
                Object o = messageContext.getProperty(org.apache.axis2.context.MessageContext.TRANSPORT_HEADERS);
                Map headers = (Map) o;
                if (headers != null) {
                    headers.put(HTTP.CONTENT_TYPE, value);
                }
            }
        }

        /**
         * {@inheritDoc}
         */
        public Set getPropertyKeySet() {
            return mc.getPropertyKeySet();
        }

        /**
         * {@inheritDoc}
         */
        public Mediator getMainSequence() {
            return mc.getMainSequence();
        }

        /**
         * {@inheritDoc}
         */
        public Mediator getFaultSequence() {
            return mc.getFaultSequence();
        }

        /**
         * {@inheritDoc}
         */
        public Mediator getSequence(String key) {
            return mc.getSequence(key);
        }

        /**
         * {@inheritDoc}
         */
        public OMElement getFormat(String s) {
            return mc.getFormat(s);
        }

        /**
         * {@inheritDoc}
         */
        public Endpoint getEndpoint(String key) {
            return mc.getEndpoint(key);
        }

        /**
         * {@inheritDoc}
         */
        public SOAPEnvelope getEnvelope() {
            return mc.getEnvelope();
        }

        /**
         * {@inheritDoc}
         */
        public void setEnvelope(SOAPEnvelope envelope) throws AxisFault {
            mc.setEnvelope(envelope);
        }

        /**
         * {@inheritDoc}
         */
        public EndpointReference getFaultTo() {
            return mc.getFaultTo();
        }

        /**
         * {@inheritDoc}
         */
        public void setFaultTo(EndpointReference reference) {
            mc.setFaultTo(reference);
        }

        /**
         * {@inheritDoc}
         */
        public EndpointReference getFrom() {
            return mc.getFrom();
        }

        /**
         * {@inheritDoc}
         */
        public void setFrom(EndpointReference reference) {
            mc.setFrom(reference);
        }

        /**
         * {@inheritDoc}
         */
        public String getMessageID() {
            return mc.getMessageID();
        }

        /**
         * {@inheritDoc}
         */
        public void setMessageID(String string) {
            mc.setMessageID(string);
        }

        /**
         * {@inheritDoc}
         */
        public RelatesTo getRelatesTo() {
            return mc.getRelatesTo();
        }

        /**
         * {@inheritDoc}
         */
        public void setRelatesTo(RelatesTo[] reference) {
            mc.setRelatesTo(reference);
        }

        /**
         * {@inheritDoc}
         */
        public EndpointReference getReplyTo() {
            return mc.getReplyTo();
        }

        /**
         * {@inheritDoc}
         */
        public void setReplyTo(EndpointReference reference) {
            mc.setReplyTo(reference);
        }

        /**
         * {@inheritDoc}
         */
        public EndpointReference getTo() {
            return mc.getTo();
        }

        /**
         * {@inheritDoc}
         */
        public void setTo(EndpointReference reference) {
            mc.setTo(reference);
        }

        /**
         * {@inheritDoc}
         */
        public void setWSAAction(String actionURI) {
            mc.setWSAAction(actionURI);
        }

        /**
         * {@inheritDoc}
         */
        public String getWSAAction() {
            return mc.getWSAAction();
        }

        /**
         * {@inheritDoc}
         */
        public String getSoapAction() {
            return mc.getSoapAction();
        }

        /**
         * {@inheritDoc}
         */
        public void setSoapAction(String string) {
            mc.setSoapAction(string);
        }

        /**
         * {@inheritDoc}
         */
        public void setWSAMessageID(String messageID) {
            mc.setWSAMessageID(messageID);
        }

        /**
         * {@inheritDoc}
         */
        public String getWSAMessageID() {
            return mc.getWSAMessageID();
        }

        /**
         * {@inheritDoc}
         */
        public boolean isDoingMTOM() {
            return mc.isDoingMTOM();
        }

        /**
         * {@inheritDoc}
         */
        public boolean isDoingSWA() {
            return mc.isDoingSWA();
        }

        /**
         * {@inheritDoc}
         */
        public void setDoingMTOM(boolean b) {
            mc.setDoingMTOM(b);
        }

        /**
         * {@inheritDoc}
         */
        public void setDoingSWA(boolean b) {
            mc.setDoingSWA(b);
        }

        /**
         * {@inheritDoc}
         */
        public boolean isDoingPOX() {
            return mc.isDoingPOX();
        }

        /**
         * {@inheritDoc}
         */
        public void setDoingPOX(boolean b) {
            mc.setDoingPOX(b);
        }

        /**
         * {@inheritDoc}
         */
        public boolean isDoingGET() {
            return mc.isDoingGET();
        }

        /**
         * {@inheritDoc}
         */
        public void setDoingGET(boolean b) {
            mc.setDoingGET(b);
        }

        /**
         * {@inheritDoc}
         */
        public boolean isSOAP11() {
            return mc.isSOAP11();
        }

        /**
         * {@inheritDoc}
         */
        public void setResponse(boolean b) {
            mc.setResponse(b);
        }

        /**
         * {@inheritDoc}
         */
        public boolean isResponse() {
            return mc.isResponse();
        }

        /**
         * {@inheritDoc}
         */
        public void setFaultResponse(boolean b) {
            mc.setFaultResponse(b);
        }

        /**
         * {@inheritDoc}
         */
        public boolean isFaultResponse() {
            return mc.isFaultResponse();
        }

        /**
         * {@inheritDoc}
         */
        public int getTracingState() {
            return mc.getTracingState();
        }

        /**
         * {@inheritDoc}
         */
        public void setTracingState(int tracingState) {
            mc.setTracingState(tracingState);
        }

        /**
         * {@inheritDoc}
         */
        public Stack<FaultHandler> getFaultStack() {
            return mc.getFaultStack();
        }

        /**
         * {@inheritDoc}
         */
        public void pushFaultHandler(FaultHandler fault) {
            mc.pushFaultHandler(fault);
        }

        /**
         * {@inheritDoc}
         */
        public void pushContinuationState(ContinuationState continuationState) {
            mc.pushContinuationState(continuationState);
        }

        /**
         * {@inheritDoc}
         */
        public Stack<ContinuationState> getContinuationStateStack() {
            return mc.getContinuationStateStack();
        }

        /**
         * {@inheritDoc}
         */
        public boolean isContinuationEnabled() {
            return false;
        }

        /**
         * {@inheritDoc}
         */
        public void setContinuationEnabled(boolean contStateStackEnabled) {
            mc.setContinuationEnabled(contStateStackEnabled);
        }

        /**
         * {@inheritDoc}
         */
        public Log getServiceLog() {
            return LogFactory.getLog(CommonScriptMessageContext.class);
        }

        /**
         * {@inheritDoc}
         */
        public Mediator getSequenceTemplate(String key) {
            return mc.getSequenceTemplate(key);
        }

        /**
         * Serialize json payload.
         *
         * @param obj Json object which required to be serialized
         */
        private String serializeJSON(Object obj) {
            StringWriter json = new StringWriter();
            if (obj instanceof Wrapper) {
                obj = ((Wrapper) obj).unwrap();
            }

            if (obj instanceof NativeObject) {
                json.append("{");
                NativeObject o = (NativeObject) obj;
                Object[] ids = o.getIds();
                boolean first = true;
                for (Object id : ids) {
                    String key = (String) id;
                    Object value = o.get((String) id, o);
                    if (!first) {
                        json.append(", ");
                    } else {
                        first = false;
                    }
                    json.append("\"").append(key).append("\" : ").append(serializeJSON(value));
                }
                json.append("}");
            } else if (obj instanceof NativeArray) {
                json.append("[");
                NativeArray o = (NativeArray) obj;
                Object[] ids = o.getIds();
                boolean first = true;
                for (Object id : ids) {
                    Object value = o.get((Integer) id, o);
                    if (!first) {
                        json.append(", ");
                    } else {
                        first = false;
                    }
                    json.append(serializeJSON(value));
                }
                json.append("]");
            } else if (obj instanceof Object[]) {
                json.append("[");
                boolean first = true;
                for (Object value : (Object[]) obj) {
                    if (!first) {
                        json.append(", ");
                    } else {
                        first = false;
                    }
                    json.append(serializeJSON(value));
                }
                json.append("]");

            } else if (obj instanceof String) {
                json.append("\"").append(obj.toString()).append("\"");
            } else if (obj instanceof Integer ||
                    obj instanceof Long ||
                    obj instanceof Float ||
                    obj instanceof Double ||
                    obj instanceof Short ||
                    obj instanceof BigInteger ||
                    obj instanceof BigDecimal ||
                    obj instanceof Boolean) {
                json.append(obj.toString());
            } else {
                json.append("{}");
            }
            return json.toString();
        }

        /**
         * Saves the payload of this message context as a JSON payload.
         *
         * @param jsonPayload Javascript native object to be set as the message body
         * @throws ScriptException in case of creating a JSON object out of the javascript native object.
         */
        @Override
        public void setPayloadJSON(Object jsonPayload) throws ScriptException {
            org.apache.axis2.context.MessageContext messageContext;
            messageContext = ((Axis2MessageContext) mc).getAxis2MessageContext();

            byte[] json = {'{', '}'};
            if (jsonPayload instanceof String) {
                json = jsonPayload.toString().getBytes();
            } else if (jsonPayload != null) {
                try {
                    ByteArrayOutputStream out = new ByteArrayOutputStream();
                    serializeJson(jsonPayload, out);
                    json = out.toByteArray();
                } catch (IOException e) {
                    logger.error("#setPayloadJSON. Could not retrieve bytes from JSON object.", e);
                }
            }
            // save this JSON object as the new payload.
            try {
                JsonUtil.getNewJsonPayload(messageContext, json, 0, json.length, true, true);
            } catch (AxisFault axisFault) {
                throw new ScriptException(axisFault);
            }
            //JsonUtil.setContentType(messageContext);
            Object jsonObject = scriptEngine.eval(JsonUtil.newJavaScriptSourceReader(messageContext));
            setJsonObject(mc, jsonObject);
        }

        /**
         * Serialize json payload and writes to output stream.
         *
         * @param obj Json object which required to be serialized
         * @param out Output stream which is required to be written with serialized json
         */
        private void serializeJson(Object obj, OutputStream out) throws IOException {
            if (out == null) {
                logger.warn("#serializeJson. Did not serialize JSON object. Object: " + obj + "  Stream: " + out);
                return;
            }
            if (obj instanceof Wrapper) {
                obj = ((Wrapper) obj).unwrap();
            }
            if (obj == null) {
                out.write("null".getBytes());
            } else if (obj instanceof NativeObject) {
                out.write('{');
                NativeObject o = (NativeObject) obj;
                Object[] ids = o.getIds();
                boolean first = true;
                for (Object id : ids) {
                    String key = (String) id;
                    Object value = o.get((String) id, o);
                    if (!first) {
                        out.write(',');
                        out.write(' ');
                    } else {
                        first = false;
                    }
                    out.write('"');
                    out.write(key.getBytes());
                    out.write('"');
                    out.write(':');
                    serializeJson(value, out);
                }
                out.write('}');
            } else if (obj instanceof NativeArray) {
                out.write('[');
                NativeArray o = (NativeArray) obj;
                Object[] ids = o.getIds();
                boolean first = true;
                for (Object id : ids) {
                    Object value = o.get((Integer) id, o);
                    if (!first) {
                        out.write(',');
                        out.write(' ');
                    } else {
                        first = false;
                    }
                    serializeJson(value, out);
                }
                out.write(']');
            } else if (obj instanceof Object[]) {
                out.write('[');
                boolean first = true;
                for (Object value : (Object[]) obj) {
                    if (!first) {
                        out.write(',');
                        out.write(' ');
                    } else {
                        first = false;
                    }
                    serializeJson(value, out);
                }
                out.write(']');
            } else if (obj instanceof String) {
                out.write('"');
                out.write(((String) obj).getBytes());
                out.write('"');
            } else if (obj instanceof ConsString) {
                //This class represents a string composed of two components using the "+" operator
                //in java script with rhino7 upward. ex:var str = "val1" + "val2";
                out.write('"');
                out.write((((ConsString) obj).toString()).getBytes());
                out.write('"');
            } else if (obj instanceof Integer ||
                    obj instanceof Long ||
                    obj instanceof Float ||
                    obj instanceof Double ||
                    obj instanceof Short ||
                    obj instanceof BigInteger ||
                    obj instanceof BigDecimal ||
                    obj instanceof Boolean) {
                out.write(obj.toString().getBytes());
            } else {
                out.write('{');
                out.write('}');
            }
        }

        /**
         * {@inheritDoc}
         */
    	public Mediator getDefaultConfiguration(String arg0) {
    	   return mc.getDefaultConfiguration(arg0);
        }

        /**
         * {@inheritDoc}
         */
        public String getMessageString() {
            return mc.getMessageString();
        }

        /**
         * {@inheritDoc}
         */
        public void setMessageFlowTracingState(int state) {
            mc.setMessageFlowTracingState(state);
        }

        /**
         * {@inheritDoc}
         */
        public int getMessageFlowTracingState() {
            return SynapseConstants.TRACING_OFF;
        }

        @Override
        public Object getVariable(String key) {

            return mc.getVariable(key);
        }

        @Override
        public void setVariable(String key, Object value) {

            if (value instanceof XMLObject) {
                OMElement omElement = null;
                try {
                    omElement = xmlHelper.toOMElement(value);
                } catch (ScriptException e) {
                    mc.setVariable(key, value);
                }
                if (omElement != null) {
                    mc.setVariable(key, omElement);
                }
            } else {
                mc.setVariable(key, value);
            }
        }

        @Override
        public Set getVariableKeySet() {

            return mc.getVariableKeySet();
        }
    }