jar包冲突,导致tomcat启动失败

把项目重新部署，出现这个错误

Exception starting filter struts2

Unable to load configuration. - [unknown location]

 at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:431)

 at org.apache.struts2.dispatcher.ng.InitOperations.initDispatcher(InitOperations.java:69)

 at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.init(StrutsPrepareAndExecuteFilter.java:51)

 at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:275)

 at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:397)

 at org.apache.catalina.core.ApplicationFilterConfig.(ApplicationFilterConfig.java:108)

 at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:3800)

 at org.apache.catalina.core.StandardContext.start(StandardContext.java:4450)

 at org.apache.catalina.startup.HostConfig.checkResources(HostConfig.java:1173)

 at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1271)

 at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:296)

 at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)

 at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1337)

 at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1601)

 at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1610)

 at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1590)

 at java.lang.Thread.run(Thread.java:619)

Caused by: Unable to load configuration. - [unknown location]

 at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:58)

 at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:374)

 at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:418)

 ... 16 more

Caused by: Caught exception while loading file struts-default.xml - [unknown location]

 at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.loadConfigurationFiles(XmlConfigurationProvider.java:902)

 at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.loadDocuments(XmlConfigurationProvider.java:143)

 at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.init(XmlConfigurationProvider.java:110)

 at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:168)

 at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:55)

 ... 18 more

Caused by: java.lang.ClassCastException: org.apache.xerces.parsers.XML11Configuration cannot be cast to org.apache.xerces.xni.parser.XMLParserConfiguration

 at org.apache.xerces.parsers.DOMParser.(Unknown Source)

 at org.apache.xerces.parsers.DOMParser.(Unknown Source)

 at org.apache.xerces.jaxp.DocumentBuilderImpl.(Unknown Source)

 at org.apache.xerces.jaxp.DocumentBuilderFactoryImpl.newDocumentBuilder(Unknown Source)

 at com.sun.org.apache.xalan.internal.xsltc.trax.SAX2DOM.createDocument(SAX2DOM.java:326)

 at com.sun.org.apache.xalan.internal.xsltc.trax.SAX2DOM.(SAX2DOM.java:85)

 at com.sun.org.apache.xalan.internal.xsltc.runtime.output.TransletOutputHandlerFactory.getSerializationHandler(TransletOutputHandlerFactory.java:187)

 at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.getOutputHandler(TransformerImpl.java:392)

 at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerHandlerImpl.setResult(TransformerHandlerImpl.java:137)

 at com.opensymphony.xwork2.util.DomHelper$DOMBuilder.setup(DomHelper.java:205)

 at com.opensymphony.xwork2.util.DomHelper$DOMBuilder.(DomHelper.java:190)

 at com.opensymphony.xwork2.util.DomHelper$DOMBuilder.(DomHelper.java:181)

 at com.opensymphony.xwork2.util.DomHelper$DOMBuilder.(DomHelper.java:167)

 at com.opensymphony.xwork2.util.DomHelper.parse(DomHelper.java:107)

 at com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.loadConfigurationFiles(XmlConfigurationProvider.java:3)

 ... 22 more

后面一查，是xerces-2.6.2.jar惹的祸

把这个jar包删除就可以了！

原因：

jar包有冲突, 应该是XML解析包有冲突. 检查发布后的WEB-INF/lib有两个XML解析包:xml-apis.jar和xerces-2.6.2.jar 这种错误真正原因不是JDK 6和Struts 2冲突, 而是MyEclipse Hibernate 类库中多了两个包: xml-apis.jar和xerces-2.6.2.jar,这两个包的功能和JDK的冲突了. 解决办法: 1. 删除发布后目录的 WEB-INF/lib/ 下的xerces-2.6.2.jar这个文件; 2. 或者使用JDK1.5来启动Tomcat 6.

前面还有个asm-2.2.3和 sam 他们也冲突  在ssh搭配时。注意：