Question

我在我的项目中使用spring集成。我想分别将<response>和</response>作为字符串附加到我的有效负载之前和之后。我正在使用int:transformer来执行此操作。以下是一段代码：

<int:transformer    expression="'<response>' + payload + '</response>'"/>

但是当我使用上面的表达式时，我得到以下异常：

Caused by: org.xml.sax.SAXParseException: The value of attribute "expression" associated with an element type "null" must not contain the '<' character.
    at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(Unknown Source)
    at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.fatalError(Unknown Source)
    at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(Unknown Source)
    at com.sun.org.apache.xerces.internal.impl.XMLScanner.reportFatalError(Unknown Source)
    at com.sun.org.apache.xerces.internal.impl.XMLScanner.scanAttributeValue(Unknown Source)
    at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.scanAttribute(Unknown Source)
    at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.scanStartElement(Unknown Source)
    at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(Unknown Source)
    at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source)
    at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(Unknown Source)
    at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
    at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
    at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
    at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
    at com.sun.org.apache.xerces.internal.parsers.DOMParser.parse(Unknown Source)
    at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse(Unknown Source)
    at org.springframework.beans.factory.xml.DefaultDocumentLoader.loadDocument(DefaultDocumentLoader.java:75)
    at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:388)
    ... 58 more

有谁可以告诉我expression应该如何完成我的任务？

Answer 1

像这样：

<int:transformer expression="'&lt;response>' + payload + '&lt;/response>'"/>

由于您在XML中使用XML定义字符串文字，因此您应该转义那些代表XML语言的符号。

int：变换器表达式错误 - 属性＆＃34;表达式＆＃34;的值与元素类型相关联＆＃34; null＆＃34;不得包含＆＃39;＆lt;＆＃39;字符

1 个答案: