迭代调解器中的错误：Axis2Sender 发送回消息 org.apache.axis2.AxisFault 的意外错误答案

【问题标题】：Error in iterate mediator:Axis2Sender Unexpected error sending message back org.apache.axis2.AxisFault迭代调解器中的错误：Axis2Sender 发送回消息 org.apache.axis2.AxisFault 的意外错误
【发布时间】：2017-11-17 16:24:59
【问题描述】：

我正在使用 wso2esb 4.7.0 和 wso2dss 3.0.0。在这里我创建了一个代理服务并希望使用有效负载工厂调解器显示一条消息。我的配置包含迭代器调解器。我必须在表中插入值数组然后显示一条消息，如 Rows 已成功插入数据库。我的 insequence 迭代配置如下：

  <iterate continueParent="true"
                  id="Readings"
                  expression="//ReadingsLiteTaildto">
            <target>
               <sequence>
                  <property name="userid" expression="get-property('userid')"/>
                  <property name="usergroupid" expression="get-property('usergroupid')"/>
                  <property name="slno" expression="//slno/text()"/>
                  <property name="type" expression="//type/text()"/>
                  <payloadFactory>
                     <format>
                        <p:Capp_musergroupdetails_insertion_op xmlns:p="http://ws.wso2.org/dataservice">
                           <p:usergroupid>$1</p:usergroupid>
                           <p:slno>$2</p:slno>
                           <p:userid>$3</p:userid>
                           <p:type>$4</p:type>
                        </p:Capp_musergroupdetails_insertion_op>
                     </format>
                     <args>
                        <arg evaluator="xml" expression="get-property('usergroupid')"/>
                        <arg evaluator="xml" expression="get-property('slno')"/>
                        <arg evaluator="xml" expression="get-property('userid')"/>
                        <arg evaluator="xml" expression="get-property('type')"/>
                     </args>
                  </payloadFactory>
                  <property name="FORCE_SC_ACCEPTED" value="true" scope="axis2"/>
                  <property name="messageType" value="application/json" scope="axis2"/>
                  <send receive="Capp_UserGroupDetail_Seq">
                     <endpoint>
                        <address uri="http://192.168.1.23:9764/services/CappMuserDataservice/"/>
                     </endpoint>
                  </send>
               </sequence>
            </target>
         </iterate>

序列配置为：

equence xmlns="http://ws.apache.org/ns/synapse" name="Capp_UserGroupDetail_Seq" onError="fault">
   <property name="CONTENT_TYPE" value="application/json" scope="axis2" type="STRING"/>
   <property name="FORCE_ERROR_ON_SOAP_FAULT" value="true"/>
   <property name="HTTP_METHOD" value="POST" scope="axis2" type="STRING"/>
   <property name="RESPONSE" value="true" scope="default" type="STRING"/>
   <property name="NO_ENTITY_BODY" action="remove" scope="axis2"/>
   <property xmlns:ns="http://org.apache.synapse/xsd" xmlns:h="http://ws.wso2.org/dataservice" name="usergroupdetailid" expression="//usergroupdetailid/text()" scope="default" type="STRING"/>
   <log>
      <property xmlns:ns="http://org.apache.synapse/xsd" name="usergroupdetailid" expression="get-property('usergroupdetailid')"/>
      <property xmlns:ns="http://org.apache.synapse/xsd" name="usergroupid" expression="get-property('usergroupid')"/>
      <property xmlns:ns="http://org.apache.synapse/xsd" name="userid" expression="get-property('userid')"/>
   </log>
   <payloadFactory>
      <format>
         <ResponseJSON xmlns="">
            <Body>
               <Datalist>
                  <Data>Successfully Rows inserted</Data>
               </Datalist>
            </Body>
            <Status>200</Status>
         </ResponseJSON>
      </format>
   </payloadFactory>
   <log level="full"/>
   <property name="messageType" value="application/json" scope="axis2"/>
   <send/>
   <property name="FORCE_ERROR_ON_SOAP_FAULT" value="true" scope="default" type="STRING"/>
</sequence>

但它会在服务器端出现错误，例如：

INFO - LogMediator To: http://www.w3.org/2005/08/addressing/anonymous, WSAction: , SOAPAction: , MessageID: urn:uuid:be41c3c9-f9c1-4ce9-933e-78b48e215601, Direction: response, usergroupdetailid = 370568479314543786, usergroupid = 370568478945445032, userid = 370568478735729831
[2014-05-27 12:23:25,165]  INFO - LogMediator To: http://www.w3.org/2005/08/addressing/anonymous, WSAction: , SOAPAction: , MessageID: urn:uuid:be41c3c9-f9c1-4ce9-933e-78b48e215601, Direction: response, Envelope: <?xml version='1.0' encoding='utf-8'?><soapenv:Envelope xmlns:soapenv="http://www.w3.org/2003/05/soap-envelope"><soapenv:Body><ResponseJSON><Body><Datalist><Data>Successfully Rows inserted</Data></Datalist></Body><Status>200</Status></ResponseJSON></soapenv:Body></soapenv:Envelope>
[2014-05-27 12:23:25,167]  INFO - LogMediator To: http://www.w3.org/2005/08/addressing/anonymous, WSAction: , SOAPAction: , MessageID: urn:uuid:06cf72eb-2aed-483b-81ce-3cbfefd0f511, Direction: response, Envelope: <?xml version='1.0' encoding='utf-8'?><soapenv:Envelope xmlns:soapenv="http://www.w3.org/2003/05/soap-envelope"><Body/></soapenv:Envelope>
[2014-05-27 12:23:25,167] ERROR - PassThroughHttpSender Failed to submit the response
java.lang.NullPointerException
    at org.codehaus.jettison.mapped.MappedXMLStreamWriter.writeEndDocument(MappedXMLStreamWriter.java:189)
    at org.apache.axis2.json.AbstractJSONMessageFormatter.writeTo(AbstractJSONMessageFormatter.java:194)
    at org.apache.synapse.transport.passthru.PassThroughHttpSender.submitResponse(PassThroughHttpSender.java:440)
    at org.apache.synapse.transport.passthru.PassThroughHttpSender.invoke(PassThroughHttpSender.java:254)
    at org.apache.axis2.engine.AxisEngine.send(AxisEngine.java:442)
    at org.apache.synapse.core.axis2.Axis2Sender.sendBack(Axis2Sender.java:161)
    at org.apache.synapse.core.axis2.Axis2SynapseEnvironment.send(Axis2SynapseEnvironment.java:308)
    at org.apache.synapse.mediators.builtin.SendMediator.mediate(SendMediator.java:92)
    at org.apache.synapse.mediators.AbstractListMediator.mediate(AbstractListMediator.java:71)
    at org.apache.synapse.mediators.base.SequenceMediator.mediate(SequenceMediator.java:114)
    at org.apache.synapse.core.axis2.Axis2SynapseEnvironment.injectMessage(Axis2SynapseEnvironment.java:239)
    at org.apache.synapse.core.axis2.SynapseCallbackReceiver.handleMessage(SynapseCallbackReceiver.java:443)
    at org.apache.synapse.core.axis2.SynapseCallbackReceiver.receive(SynapseCallbackReceiver.java:166)
    at org.apache.axis2.engine.AxisEngine.receive(AxisEngine.java:180)
    at org.apache.synapse.transport.passthru.ClientWorker.run(ClientWorker.java:222)
    at org.apache.axis2.transport.base.threads.NativeWorkerPool$1.run(NativeWorkerPool.java:172)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1146)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:679)
[2014-05-27 12:23:25,168] ERROR - Axis2Sender Unexpected error sending message back
org.apache.axis2.AxisFault: Failed to submit the response
    at org.apache.synapse.transport.passthru.PassThroughHttpSender.handleException(PassThroughHttpSender.java:501)
    at org.apache.synapse.transport.passthru.PassThroughHttpSender.invoke(PassThroughHttpSender.java:256)
    at org.apache.axis2.engine.AxisEngine.send(AxisEngine.java:442)
    at org.apache.synapse.core.axis2.Axis2Sender.sendBack(Axis2Sender.java:161)
    at org.apache.synapse.core.axis2.Axis2SynapseEnvironment.send(Axis2SynapseEnvironment.java:308)
    at org.apache.synapse.mediators.builtin.SendMediator.mediate(SendMediator.java:92)
    at org.apache.synapse.mediators.AbstractListMediator.mediate(AbstractListMediator.java:71)
    at org.apache.synapse.mediators.base.SequenceMediator.mediate(SequenceMediator.java:114)
    at org.apache.synapse.core.axis2.Axis2SynapseEnvironment.injectMessage(Axis2SynapseEnvironment.java:239)
    at org.apache.synapse.core.axis2.SynapseCallbackReceiver.handleMessage(SynapseCallbackReceiver.java:443)
    at org.apache.synapse.core.axis2.SynapseCallbackReceiver.receive(SynapseCallbackReceiver.java:166)
    at org.apache.axis2.engine.AxisEngine.receive(AxisEngine.java:180)
    at org.apache.synapse.transport.passthru.ClientWorker.run(ClientWorker.java:222)
    at org.apache.axis2.transport.base.threads.NativeWorkerPool$1.run(NativeWorkerPool.java:172)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1146)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:679)
Caused by: java.lang.NullPointerException
    at org.codehaus.jettison.mapped.MappedXMLStreamWriter.writeEndDocument(MappedXMLStreamWriter.java:189)
    at org.apache.axis2.json.AbstractJSONMessageFormatter.writeTo(AbstractJSONMessageFormatter.java:194)
    at org.apache.synapse.transport.passthru.PassThroughHttpSender.submitResponse(PassThroughHttpSender.java:440)
    at org.apache.synapse.transport.passthru.PassThroughHttpSender.invoke(PassThroughHttpSender.java:254)
    ... 15 more
[2014-05-27 12:23:25,169]  INFO - LogMediator To: http://www.w3.org/2005/08/addressing/anonymous, WSAction: , SOAPAction: , MessageID: urn:uuid:ba684be3-b7bc-46bd-9c21-66495061c97d, Direction: response, MESSAGE = Executing default 'fault' sequence, ERROR_CODE = 0, ERROR_MESSAGE = Unexpected error sending message back, Envelope: <?xml version='1.0' encoding='utf-8'?><soapenv:Envelope xmlns:soapenv="http://www.w3.org/2003/05/soap-envelope"><Body/></soapenv:Envelope>

他们的顺序有什么问题吗？请告诉我。

【问题讨论】：

我可以在您的跟踪 (wso2-carbon.log) 中看到 3 个日志条目：对于最后一个 (message id urn:uuid:06cf72eb-2aed-483b-81ce-3cbfefd0f511)，soap body 是空：这个日志是从哪里来的？当 AbstractJSONMessageFormatter 找不到数据时，这不是 NullPointer 的原因吗？
谢谢Jean..日志调解器会导致NullPointerException吗？

标签： nullpointerexception wso2 wso2esb axis2 wso2dss

【解决方案1】：

NullPointerException 是由空响应引起的：Soap 主体为空（请参阅第 3 个日志条目）并且与 application/json (org.apache.axis2.json.JSONMessageFormatter) 关联的消息格式化程序无法处理它

【讨论】：