Question

我有这个Mule ESB测试项目：

<?xml version="1.0" encoding="UTF-8"?>

<mule xmlns="http://www.mulesoft.org/schema/mule/core" xmlns:doc="http://www.mulesoft.org/schema/mule/documentation" xmlns:spring="http://www.springframework.org/schema/beans" version="CE-3.4.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-current.xsd
http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd">
    <flow name="testFlow1" doc:name="testFlow1">
        <poll frequency="60000" doc:name="Poll">
            <flow-ref name="testFlow2" doc:name="Flow Reference"/>
        </poll>
        <processor ref="" />
    </flow>
    <sub-flow name="testFlow2" doc:name="testFlow2">
                    <set-payload value="&lt;root&gt;
   &lt;entry&gt;
      &lt;key&gt;mobile_phone&lt;/key&gt;
      &lt;value&gt;380996547889&lt;/value&gt;
   &lt;/entry&gt;
&lt;/root&gt;" doc:name="Set Payload"/>
                <logger message="XML: #[message.payload]" level="INFO" doc:name="Log XML"/>
                <logger message="MobilePhone: #[xpath('/root/entry/key[text()=&quot;mobile_phone&quot;]/../value/text()')]" level="INFO" doc:name="Log Properties"/>
    </sub-flow>
</mule>

启动后我在日志中出现此错误：

**********************************************************************
* Application: test                                                  *
* OS encoding: UTF-8, Mule encoding: UTF-8                           *
*                                                                    *
* Agents Running:                                                    *
*   JMX Agent                                                        *
**********************************************************************
INFO  2013-11-18 14:39:39,190 [main] org.mule.module.launcher.MuleDeploymentService: 
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+ Started app 'test'                                       +
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
INFO  2013-11-18 14:39:40,270 [[test].connector.polling.mule.default.receiver.01] org.mule.api.processor.LoggerMessageProcessor: XML: <root>    <entry>       <key>mobile_phone</key>       <value>380996547889</value>    </entry> </root>
ERROR 2013-11-18 14:39:40,545 [[test].connector.polling.mule.default.receiver.01] org.mule.exception.DefaultMessagingExceptionStrategy: 
********************************************************************************
Message               : Execution of the expression "xpath('/root/entry/key[text()="mobile_phone"]/../value/text()').getText()" failed. (org.mule.api.expression.ExpressionRuntimeException). Message payload is of type: String
Code                  : MULE_ERROR--2
--------------------------------------------------------------------------------
Exception stack is:
1. [Error: unable to resolve method: java.util.ArrayList.getText() [arglength=0]]
[Near : {... xpath('/root/entry/key[text()= ....}]
             ^
[Line: 1, Column: 1] (org.mvel2.PropertyAccessException)
  org.mvel2.optimizers.impl.refl.ReflectiveAccessorOptimizer:1078 (null)
2. Execution of the expression "xpath('/root/entry/key[text()="mobile_phone"]/../value/text()').getText()" failed. (org.mule.api.expression.ExpressionRuntimeException)
  org.mule.el.mvel.MVELExpressionLanguage:218 (http://www.mulesoft.org/docs/site/current3/apidocs/org/mule/api/expression/ExpressionRuntimeException.html)
3. Execution of the expression "xpath('/root/entry/key[text()="mobile_phone"]/../value/text()').getText()" failed. (org.mule.api.expression.ExpressionRuntimeException). Message payload is of type: String (org.mule.api.MessagingException)
  org.mule.execution.ExceptionToMessagingExceptionExecutionInterceptor:35 (http://www.mulesoft.org/docs/site/current3/apidocs/org/mule/api/MessagingException.html)
--------------------------------------------------------------------------------
Root Exception stack trace:
[Error: unable to resolve method: java.util.ArrayList.getText() [arglength=0]]
[Near : {... xpath('/root/entry/key[text()= ....}]
             ^
[Line: 1, Column: 1]
    at org.mvel2.optimizers.impl.refl.ReflectiveAccessorOptimizer.getMethod(ReflectiveAccessorOptimizer.java:1078)
    at org.mvel2.optimizers.impl.refl.ReflectiveAccessorOptimizer.getMethod(ReflectiveAccessorOptimizer.java:987)
    at org.mvel2.optimizers.impl.refl.ReflectiveAccessorOptimizer.compileGetChain(ReflectiveAccessorOptimizer.java:377)
    + 3 more (set debug level logging or '-Dmule.verbose.exceptions=true' for everything)
********************************************************************************

即。由于未知原因，标记value的测试值的XPath函数返回ArrayList对象而不是String。

有人知道如何强制XPath返回String对象吗？

Answer 1

通过在XML中添加<?xml version="1.0" encoding="utf-8"?>标头解决。没有这个Mule XPath函数表现得很奇怪。

Mule ESB XPath函数返回ArrayList而不是String

1 个答案: