关于使用Axis2 webservice 处理Fault响应时抛org.apache.axis2.AxisFault的分析

使用Axis2这个框架进行webservice协议通讯，期间出了个问题，我（CLIENT）请求后，当服务端返回符合协议的SOAP异常报文，例如 ...

我的程序直接抛org.apache.axis2.AxisFault异常，导致连服务端给我们的报文都没有接收成功。 

--请注意，是我连报文都没有接收成功，而不是接收成功后我解析失败了。

try {
         ServiceClient serviceClient = new ServiceClient();
         Options options = new Options();
         //设置超时时间，单位毫秒
         options.setTimeOutInMilliSeconds(this.wsTimeOut);
           options.setTransportInProtocol(Constants.TRANSPORT_HTTP);
           options.setTo(new EndpointReference(this.wsEndpointAddress));
           options.setSoapVersionURI(org.apache.axiom.soap.SOAP12Constants.SOAP_ENVELOPE_NAMESPACE_URI);
           options.setAction(this.wsMethod);
           MessageContext requetMessageContext = new MessageContext();
           SOAPEnvelope env = this.getRequestEnvelope();
           log.info("version : "+ env.getVersion().getEnvelopeURI());
            requetMessageContext.setEnvelope(env);
            
            OperationClient opClient = serviceClient.createClient(ServiceClient.ANON_OUT_IN_OP);
            opClient.addMessageContext(requetMessageContext);
            opClient.setOptions(options);
            opClient.execute(true);
            MessageContext rspMC = opClient.getMessageContext("In");
            response = rspMC.getEnvelope().getBody().getFirstElement();
         log.info("应答报文: "+ rspMC.getEnvelope());
      } catch (AxisFault e) {
         this.errRspDesc = "xxxxx";
         log.error("soapDispatch AxisFault!");
         throw e;
      } catch (Exception e) {
         this.errRspDesc = "xxxxxxxxxxxxx！";
         log.error("soapDispatch Exception!");
         throw e;
      }

当执行到发送请求opClient.execute(true); 

服务端成功返回格式正常的SOAP异常报文，此时程序直接抛异常，走不到下面rspMC的获取，也就拿不到响应报文。

经过一段时间的查看Axis2源码，终于找到原因。

从opClient.execute(true); 入手，可以看到

 public final void execute(boolean block) throws AxisFault {
        this.sc.setLastOperationContext(this.oc);
        this.executeImpl(block);
    }

再看this.executeImpl(block);

 public void executeImpl(boolean block) throws AxisFault {
        if(log.isDebugEnabled()) {
            log.debug("Entry: OutInAxisOperationClient::execute, " + block);
        }

        if(this.completed) {
            throw new AxisFault(Messages.getMessage("mepiscomplted"));
        } else {
            ConfigurationContext cc = this.sc.getConfigurationContext();
            MessageContext mc = this.oc.getMessageContext("Out");
            if(mc == null) {
                throw new AxisFault(Messages.getMessage("outmsgctxnull"));
            } else {
                this.prepareMessageContext(cc, mc);
                if(this.options.getTransportIn() == null && mc.getTransportIn() == null) {
                    mc.setTransportIn(ClientUtils.inferInTransport(cc.getAxisConfiguration(), this.options, mc));
                } else if(mc.getTransportIn() == null) {
                    mc.setTransportIn(this.options.getTransportIn());
                }

                boolean useAsync = false;
                if(!mc.getOptions().isUseSeparateListener()) {
                    Boolean replyTo = (Boolean)mc.getProperty("UseAsyncOperations");
                    if(log.isDebugEnabled()) {
                        log.debug("OutInAxisOperationClient: useAsyncOption " + replyTo);
                    }

                    if(replyTo != null) {
                        useAsync = replyTo.booleanValue();
                    }
                }

                EndpointReference replyTo1 = mc.getReplyTo();
                if(replyTo1 != null) {
                    if(replyTo1.hasNoneAddress()) {
                        throw new AxisFault(replyTo1.getAddress() + "" + " can not be used with OutInAxisOperationClient , user either " + "fireAndForget or sendRobust)");
                    }

                    if(replyTo1.isWSAddressingAnonymous() && replyTo1.getAllReferenceParameters() != null) {
                        mc.setProperty("includeOptionalHeaders", Boolean.TRUE);
                    }

                    String customReplyTo = (String)this.options.getProperty(Options.CUSTOM_REPLYTO_ADDRESS);
                    if(!Options.CUSTOM_REPLYTO_ADDRESS_TRUE.equals(customReplyTo) && !replyTo1.hasAnonymousAddress()) {
                        useAsync = true;
                    }
                }

                if(!useAsync && !mc.getOptions().isUseSeparateListener()) {
                    if(block) {
                        this.send(mc);
                        this.completed = true;
                    } else {
                        this.sc.getConfigurationContext().getThreadPool().execute(new OutInAxisOperationClient.NonBlockingInvocationWorker(this.callback, mc, this.axisCallback));
                    }
                } else {
                    this.sendAsync(useAsync, mc);
                }

            }
        }
    }

进send(mc)方法

 protected MessageContext send(MessageContext msgContext) throws AxisFault {
        MessageContext responseMessageContext = msgContext.getConfigurationContext().createMessageContext();
        responseMessageContext.setServerSide(false);
        responseMessageContext.setOperationContext(msgContext.getOperationContext());
        responseMessageContext.setOptions(new Options(this.options));
        responseMessageContext.setMessageID(msgContext.getMessageID());
        this.addMessageContext(responseMessageContext);
        responseMessageContext.setServiceContext(msgContext.getServiceContext());
        responseMessageContext.setAxisMessage(this.axisOp.getMessage("In"));
        AxisEngine.send(msgContext);
        responseMessageContext.setDoingREST(msgContext.isDoingREST());
        responseMessageContext.setProperty("TRANSPORT_HEADERS", msgContext.getProperty("TRANSPORT_HEADERS"));
        responseMessageContext.setProperty(HTTPConstants.MC_HTTP_STATUS_CODE, msgContext.getProperty(HTTPConstants.MC_HTTP_STATUS_CODE));
        responseMessageContext.setProperty("TRANSPORT_IN", msgContext.getProperty("TRANSPORT_IN"));
        responseMessageContext.setTransportIn(msgContext.getTransportIn());
        responseMessageContext.setTransportOut(msgContext.getTransportOut());
        this.handleResponse(responseMessageContext);
        return responseMessageContext;
    }

这里就是发送请求并接收响应的地方
再看倒数第二行this.handleResponse(responseMessageContext);

   protected void handleResponse(MessageContext responseMessageContext) throws AxisFault {
        responseMessageContext.setSoapAction((String)null);
        SOAPEnvelope resenvelope;
        if(responseMessageContext.getEnvelope() == null) {
            resenvelope = TransportUtils.createSOAPMessage(responseMessageContext);
            if(resenvelope == null) {
                throw new AxisFault(Messages.getMessage("blockingInvocationExpectsResponse"));
            }

            responseMessageContext.setEnvelope(resenvelope);
        }

        resenvelope = responseMessageContext.getEnvelope();
        if(resenvelope != null) {
            AxisEngine.receive(responseMessageContext);
            if(responseMessageContext.getReplyTo() != null) {
                this.sc.setTargetEPR(responseMessageContext.getReplyTo());
            }

            resenvelope = responseMessageContext.getEnvelope();
            if((resenvelope.hasFault() || responseMessageContext.isProcessingFault()) && this.options.isExceptionToBeThrownOnSOAPFault()) {
                throw Utils.getInboundFaultFromMessageContext(responseMessageContext);
            }
        }

    }

这时，我们可以看到一个很有趣的方法， if((resenvelope.hasFault() || responseMessageContext.isProcessingFault())
总算是跟我们的异常报文有关了。跟进去看一下

  public boolean hasFault() {
        QName payloadQName = this.getPayloadQName_Optimized();
        if(payloadQName != null && "Fault".equals(payloadQName.getLocalPart())) {
            String body1 = payloadQName.getNamespaceURI();
            return "http://schemas.xmlsoap.org/soap/envelope/".equals(body1) || "http://www.w3.org/2003/05/soap-envelope".equals(body1);
        } else {
            SOAPBody body = this.getBody();
            return body == null?false:body.hasFault();
        }
    }

可以看到Axis2的内部处理机制，就是一但发现响应报文有Fault节点，它就要抛异常。总算找到源头了
那要如何解决这个问题
我们可以看到
if((resenvelope.hasFault() || responseMessageContext.isProcessingFault()) && this.options.isExceptionToBeThrownOnSOAPFault()) {
                throw Utils.getInboundFaultFromMessageContext(responseMessageContext);
            }
这里还有一个判断条件，
this.options.isExceptionToBeThrownOnSOAPFault()
当它为TRUE时才抛异常。
这就是options的一个参数，可配置，所以给我们的代码加上

options.setExceptionToBeThrownOnSOAPFault(false);

就不抛异常了，能够正常获取并解析响应报文。
总结：一切的害怕源于对代码的神秘，未知，当你把它当成自己写的代码，去反编译，去阅读，那就不会再害怕！