出现这个错误的原因是因为在web.xml注释出现了问题：
我原来写的注释是<!-- -------start--------- -->后来改成<!-- start -->就没有错误了，应该是----太多了，不识别吧。
在第几行出现了错误，信息中都有提示的。
org.xml.sax.SAXParseException: The string "--" is not permitted within comments. at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:195) at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.fatalError(ErrorHandlerWrapper.java:174) at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:388) at com.sun.org.apache.xerces.internal.impl.XMLScanner.reportFatalError(XMLScanner.java:1411) at com.sun.org.apache.xerces.internal.impl.XMLScanner.scanComment(XMLScanner.java:774) at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanComment(XMLDocumentFragmentScannerImpl.java:1036) at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2945) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:648) at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:510) at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:807) at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737) at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:107) at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205) at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522) at org.apache.tomcat.util.digester.Digester.parse(Digester.java:1642) at org.apache.catalina.startup.ContextConfig.applicationWebConfig(ContextConfig.java:365) at org.apache.catalina.startup.ContextConfig.start(ContextConfig.java:1076) at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:261) at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119) at org.apache.catalina.core.StandardContext.start(StandardContext.java:4540) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:546) at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1041) at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:964) at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:502) at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1277) at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:321) at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119) at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053) at org.apache.catalina.core.StandardHost.start(StandardHost.java:785) at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045) at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:445) at org.apache.catalina.core.StandardService.start(StandardService.java:519) at org.apache.catalina.core.StandardServer.start(StandardServer.java:710) at org.apache.catalina.startup.Catalina.start(Catalina.java:581) 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:597) at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289) at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414) 2012-3-5 14:59:43 org.apache.catalina.startup.ContextConfig applicationWebConfig 严重: Parse error in application web.xml file at jndi:/localhost/mobile_appstore/WEB-INF/web.xml org.xml.sax.SAXParseException: The string "--" is not permitted within comments. at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1231) at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522) at org.apache.tomcat.util.digester.Digester.parse(Digester.java:1642) at org.apache.catalina.startup.ContextConfig.applicationWebConfig(ContextConfig.java:365) at org.apache.catalina.startup.ContextConfig.start(ContextConfig.java:1076) at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:261) at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119) at org.apache.catalina.core.StandardContext.start(StandardContext.java:4540) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:546) at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1041) at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:964) at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:502) at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1277) at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:321) at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119) at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053) at org.apache.catalina.core.StandardHost.start(StandardHost.java:785) at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045) at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:445) at org.apache.catalina.core.StandardService.start(StandardService.java:519) at org.apache.catalina.core.StandardServer.start(StandardServer.java:710) at org.apache.catalina.startup.Catalina.start(Catalina.java:581) 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:597) at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289) at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414) 2012-3-5 14:59:43 org.apache.catalina.startup.ContextConfig applicationWebConfig 严重: Occurred at line 75 column 8 2012-3-5 14:59:43 org.apache.catalina.startup.ContextConfig start 严重: Marking this application unavailable due to previous error(s) 2012-3-5 14:59:43 org.apache.catalina.core.StandardContext start 严重: Error getConfigured 2012-3-5 14:59:43 org.apache.catalina.core.StandardContext start 严重: Context [/mobile_appstore] startup failed due to previous errors