Consume a web service method with multiple args in Mule esb

Question

Hello what I want to apply seems very simple but I don't know how, need some clarifications. here is the scenario: I want to call a web service method, this method name is find() and accept as argument an object, the object represent a composed primary key, composed by two strings an id and a type. the object -which is the primary key- representation in soap is :

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:wsd="http://wsdouane/">
   <soapenv:Header/>
   <soapenv:Body>
      <wsd:find>
         <entity>
            <id>string_1</id>
            <type>string_2</type>
         </entity>
      </wsd:find>
   </soapenv:Body>
</soapenv:Envelope>

my first idea was about reading the two args (the id and the type)from an http post request to create the wanted primary key object with a java transformer which call the primary key class constructor , then pass the created object to a soap component to creat the soap request based on the object, then call the web service with an http component and finally write the response into a file. this the resulting flow:

<flow name="testObjetFlow1" doc:name="testObjetFlow1">
    <http:inbound-endpoint exchange-pattern="one-way" host="localhost" port="8088" doc:name="HTTP"/>
    <custom-transformer class="com.test.transformer.HttpRequestToPrimaryKeyObject" doc:name="PK Object Transformer"/>
    <cxf:jaxws-client operation="find" serviceClass="douane.Douane" port="douanePort"  doc:name="SOAP"/>
    <http:outbound-endpoint exchange-pattern="request-response" method="POST" address="http://localhost:8080/ClientsDB/douane" doc:name="douaneWS"/>
    <mulexml:object-to-xml-transformer doc:name="Object to XML"/>
    <file:outbound-endpoint path="C:\MuleStudio\SandBox\output" outputPattern="#[function:datestamp:dd-MM-yy]_#[function:systime].xml " responseTimeout="10000" doc:name="Outgoing File"/>
</flow>

My custom transformer

package com.test.transformer;

import org.mule.api.MuleMessage;
import org.mule.api.transformer.TransformerException;
import org.mule.transformer.AbstractMessageTransformer;
import douane.DouanePK;
public class HttpRequestToPrimaryKeyObject extends AbstractMessageTransformer {

    @Override
    //DouanePK represent the primary key entity
    public DouanePK transformMessage(MuleMessage message, String outputEncoding)
            throws TransformerException {
        // TODO Auto-generated method stub
        String id = message.getInboundProperty("id");
        String type = message.getInboundProperty("type");

        DouanePK primKey = new DouanePK();
        dp.setId(id);
        dp.setType(type);

        return primKey;
    }

}

when I run the project I get the error

ERROR 2013-05-16 09:44:13,191 [[mediation_mod].testObjetFlow1.stage1.03] org.mule.exception.DefaultMessagingExceptionStrategy: 
********************************************************************************
Message               : Could not call org.apache.cxf.binding.soap.SoapMessage.writeObject() : Cannot marshal the XStream instance in action
---- Debugging information ----
-------------------------------
message             : Could not call org.apache.cxf.binding.soap.SoapMessage.writeObject()
cause-exception     : com.thoughtworks.xstream.converters.ConversionException
cause-message       : Cannot marshal the XStream instance in action
------------------------------- (com.thoughtworks.xstream.converters.ConversionException). Message payload is of type: byte[]
Code                  : MULE_ERROR--2
--------------------------------------------------------------------------------
Exception stack is:
1. Cannot marshal the XStream instance in action
---- Debugging information ----
------------------------------- (com.thoughtworks.xstream.converters.ConversionException)
  com.thoughtworks.xstream.converters.reflection.SelfStreamingInstanceChecker:44 (null)
2. Could not call org.apache.cxf.binding.soap.SoapMessage.writeObject() : Cannot marshal the XStream instance in action
---- Debugging information ----
-------------------------------
message             : Could not call org.apache.cxf.binding.soap.SoapMessage.writeObject()
cause-exception     : com.thoughtworks.xstream.converters.ConversionException
cause-message       : Cannot marshal the XStream instance in action
------------------------------- (com.thoughtworks.xstream.converters.ConversionException)
  com.thoughtworks.xstream.converters.reflection.SerializationMethodInvoker:140 (null)
3. Could not call org.apache.cxf.binding.soap.SoapMessage.writeObject() : Cannot marshal the XStream instance in action
---- Debugging information ----
-------------------------------
message             : Could not call org.apache.cxf.binding.soap.SoapMessage.writeObject()
cause-exception     : com.thoughtworks.xstream.converters.ConversionException
cause-message       : Cannot marshal the XStream instance in action
------------------------------- (com.thoughtworks.xstream.converters.ConversionException). Message payload is of type: byte[] (org.mule.api.transformer.TransformerMessagingException)
  org.mule.transformer.AbstractTransformer:139 (http://www.mulesoft.org/docs/site/current3/apidocs/org/mule/api/transformer/TransformerMessagingException.html)
--------------------------------------------------------------------------------
Root Exception stack trace:
com.thoughtworks.xstream.converters.ConversionException: Cannot marshal the XStream instance in action
---- Debugging information ----
-------------------------------
    at com.thoughtworks.xstream.converters.reflection.SelfStreamingInstanceChecker.marshal(SelfStreamingInstanceChecker.java:44)
    at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:69)
    at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:58)
    + 3 more (set debug level logging or '-Dmule.verbose.exceptions=true' for everything)
********************************************************************************

ERROR 2013-05-16 09:44:13,182 [[mediation_mod].testObjetFlow1.stage1.02] org.mule.exception.DefaultMessagingExceptionStrategy: 
********************************************************************************
Message               : Could not call org.apache.cxf.binding.soap.SoapMessage.writeObject() : Cannot marshal the XStream instance in action
---- Debugging information ----
-------------------------------
message             : Could not call org.apache.cxf.binding.soap.SoapMessage.writeObject()
cause-exception     : com.thoughtworks.xstream.converters.ConversionException
cause-message       : Cannot marshal the XStream instance in action
------------------------------- (com.thoughtworks.xstream.converters.ConversionException). Message payload is of type: byte[]
Code                  : MULE_ERROR--2
--------------------------------------------------------------------------------
Exception stack is:
1. Cannot marshal the XStream instance in action
---- Debugging information ----
------------------------------- (com.thoughtworks.xstream.converters.ConversionException)
  com.thoughtworks.xstream.converters.reflection.SelfStreamingInstanceChecker:44 (null)
2. Could not call org.apache.cxf.binding.soap.SoapMessage.writeObject() : Cannot marshal the XStream instance in action
---- Debugging information ----
-------------------------------
message             : Could not call org.apache.cxf.binding.soap.SoapMessage.writeObject()
cause-exception     : com.thoughtworks.xstream.converters.ConversionException
cause-message       : Cannot marshal the XStream instance in action
------------------------------- (com.thoughtworks.xstream.converters.ConversionException)
  com.thoughtworks.xstream.converters.reflection.SerializationMethodInvoker:140 (null)
3. Could not call org.apache.cxf.binding.soap.SoapMessage.writeObject() : Cannot marshal the XStream instance in action
---- Debugging information ----
-------------------------------
message             : Could not call org.apache.cxf.binding.soap.SoapMessage.writeObject()
cause-exception     : com.thoughtworks.xstream.converters.ConversionException
cause-message       : Cannot marshal the XStream instance in action
------------------------------- (com.thoughtworks.xstream.converters.ConversionException). Message payload is of type: byte[] (org.mule.api.transformer.TransformerMessagingException)
  org.mule.transformer.AbstractTransformer:139 (http://www.mulesoft.org/docs/site/current3/apidocs/org/mule/api/transformer/TransformerMessagingException.html)
--------------------------------------------------------------------------------
Root Exception stack trace:
com.thoughtworks.xstream.converters.ConversionException: Cannot marshal the XStream instance in action
---- Debugging information ----
-------------------------------
    at com.thoughtworks.xstream.converters.reflection.SelfStreamingInstanceChecker.marshal(SelfStreamingInstanceChecker.java:44)
    at com.thoughtworks.xstream.core.AbstractReferenceMarshaller.convert(AbstractReferenceMarshaller.java:69)
    at com.thoughtworks.xstream.core.TreeMarshaller.convertAnother(TreeMarshaller.java:58)
    + 3 more (set debug level logging or '-Dmule.verbose.exceptions=true' for everything)
********************************************************************************

I dont know if my logic is wrong or if there is a simple way to get the job done ?? thak you for your help.

Answer 1

First, I would not create a custom-transformer for simply instantiating a class, I would just use an expression:

<expression-transformer
    expression="#[new douane.DouanePK(message.inboundProperties.id,message.inboundProperties.type)]" />

Second, the exception you're getting comes from the inability of mulexml:object-to-xml-transformer to transform a SoapMessage object to XML using XStream (which is kind of expected). It is the responsibility of cxf:jaxws-client to do this unmarshalling in the response phase of the flow.

So you need to the mulexml:object-to-xml-transformer and the file:outbound-endpoint elements in a response element above the cxf:jaxws-client so they are processed after CXF has unmarshalled the response to the right object.

Answer 2

xml到对象的错误是由于SOAP组件引起的，在您的情况下，您可以避免使用它，而只使用和表达式转换器