Struts1.x的配置的子元素的配置顺序

1、Struts中的<struts-config>元素是Struts配置的根元素，和它对应的配置类为org.apache.struts.config.ModuleConfig类。它有8个子元素，它的DTD定义如下：

<!ELEMENT struts-config(data-sources?, form-beans?, global-exceptions?, global-forwards?, action-mappings?, controller?, message-resources*, plug-in*)

 

在struts中，配置必须按照以上的DTD指定的顺序来配置<Struts-config>元素的各个子元素，如果颠倒了这写顺序，在struts应用启动时会生成以下错误：

2010-8-15 12:47:45 org.apache.commons.digester.Digester error
严重: Parse Error at line 65 column 17: The content of element type "struts-config" must match "(display-name?,description?,data-sources?,form-beans?,global-exceptions?,global-forwards?,action-mappings?,controller?,message-resources*,plug-in*)".
org.xml.sax.SAXParseException: The content of element type "struts-config" must match "(display-name?,description?,data-sources?,form-beans?,global-exceptions?,global-forwards?,action-mappings?,controller?,message-resources*,plug-in*)".
	at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:236)
	at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.error(ErrorHandlerWrapper.java:172)
	at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:382)
	at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:316)
	at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.handleEndElement(XMLDTDValidator.java:2048)
	at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.endElement(XMLDTDValidator.java:932)
	at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.scanEndElement(XMLNSDocumentScannerImpl.java:719)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(XMLDocumentFragmentScannerImpl.java:1685)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:368)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:834)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:764)
	at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:148)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1242)
	at org.apache.commons.digester.Digester.parse(Digester.java:1827)
	at org.apache.struts.action.ActionServlet.parseModuleConfigFile(ActionServlet.java:740)
	at org.apache.struts.action.ActionServlet.initModuleConfig(ActionServlet.java:689)
	at org.apache.struts.action.ActionServlet.init(ActionServlet.java:356)
	at javax.servlet.GenericServlet.init(GenericServlet.java:212)
	at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1139)
	at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:966)
	at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:3956)
	at org.apache.catalina.core.StandardContext.start(StandardContext.java:4230)
	at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:760)
	at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:740)
	at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:544)
	at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:927)
	at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:890)
	at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:492)
	at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1150)
	at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:120)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1022)
	at org.apache.catalina.core.StandardHost.start(StandardHost.java:736)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1014)
	at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
	at org.apache.catalina.core.StandardService.start(StandardService.java:448)
	at org.apache.catalina.core.StandardServer.start(StandardServer.java:700)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:552)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:585)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:295)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:433)