一些常见异常：
//如果不用，启动时不会出错，但使用Dwr时，会抛出异常：java.lang.NoClassDefFoundError: antlr/ANTLRException antlr-2.7.2.jar //如果不用此包，在启动时会抛出： nested exception is java.lang.NoClassDefFoundError: org/objectweb/asm/Type asm.jar //如果不用此包，在启动时抛出：nested exception is java.lang.NoClassDefFoundError: org/aspectj/weaver/reflect/ReflectionWorld$ReflectionWorldException aspectjweaver.jar //如果不用此包，在启动时抛出：nested exception is java.lang.NoClassDefFoundError: net/sf/cglib/proxy/CallbackFilter cglib-2.1.3.jar //如果不用此包，在启动时抛出：nested exception is java.lang.NoClassDefFoundError: org/apache/commons/collections/SequencedHashMap commons-collections-3.1.jar //这个似乎可以不用的 commons-fileupload-1.2.1.jar //这个就不用说啦，几乎所有框架都要使用的 commons-logging-1.0.4.jar //如果不用此包会抛出：java.lang.NoClassDefFoundError: org/dom4j/DocumentException dom4j-1.6.1.jar
//不用此包，在启动时报出：java.lang.NoClassDefFoundError: javax/transaction/TransactionManager jta.jar //struts2必须 freemarker-2.3.8.jar //struts2必须 ognl-2.6.11.jar //struts2核心包 struts2-core-2.0.11.2.jar //struts2整合Spring插件 struts2-spring-plugin-2.0.11.2.jar //struts2必须 xwork-2.0.5.jar
启动异常：
17:27:14,982 ERROR [STDERR] log4j:ERROR A "org.jboss.logging.appender.FileAppender" object is not assignable to a "org.apache.log4j.Appender" variable.
17:27:14,983 ERROR [STDERR] log4j:ERROR The class "org.apache.log4j.Appender" was loaded by
17:27:14,983 ERROR [STDERR] log4j:ERROR [WebappClassLoader
delegate: false
repositories:
/WEB-INF/classes/
----------> Parent Classloader:
java.net.FactoryURLClassLoader@18ee2ee
] whereas object of type
17:27:14,983 ERROR [STDERR] log4j:ERROR "org.jboss.logging.appender.FileAppender" was loaded by [org.jboss.system.server.NoAnnotationURLClassLoader@506411].
17:27:14,983 ERROR [STDERR] log4j:ERROR Could not instantiate appender named "FILE".
原因：项目Jar包与JBoss的jar包冲突(有关日志的jar包)。
解决方法：删除项目中的有关日志的jar包。
SEVERE: Exception fixing docBase for context [/cib]
java.util.zip.ZipException: invalid END header (bad central directory offset) /oradata/mbp/tomcat6/apache-tomcat-6.0.24/webapps/cib.war
at java.util.zip.ZipFile.open(Native Method)
at java.util.zip.ZipFile.<init>(ZipFile.java:238)
at java.util.jar.JarFile.<init>(JarFile.java:165)
at java.util.jar.JarFile.<init>(JarFile.java:103)
at sun.net.www.protocol.jar.URLJarFile.<init>(URLJarFile.java:71)
at sun.net.www.protocol.jar.URLJarFile.getJarFile(URLJarFile.java:56)
at sun.net.www.protocol.jar.JarFileFactory.get(JarFileFactory.java:99)
at sun.net.www.protocol.jar.JarURLConnection.connect(JarURLConnection.java:131)
at sun.net.www.protocol.jar.JarURLConnection.getJarFile(JarURLConnection.java:98)
at org.apache.catalina.startup.ExpandWar.expand(ExpandWar.java:148)
at org.apache.catalina.startup.ContextConfig.fixDocBase(ContextConfig.java:882)
at org.apache.catalina.startup.ContextConfig.init(ContextConfig.java:1017)
at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:279)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
at org.apache.catalina.core.StandardContext.init(StandardContext.java:5439)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4215)
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:526)
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:905)
at org.apache.catalina.startup.HostConfig.deployWARs(HostConfig.java:740)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:500)
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:722)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
at org.apache.catalina.core.StandardService.start(StandardService.java:516)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
at org.apache.catalina.startup.Catalina.start(Catalina.java:593)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:615)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
Mar 22, 2012 9:10:12 AM org.apache.catalina.core.StandardContext resourcesStart
SEVERE: Error starting static Resources
java.lang.IllegalArgumentException: Invalid or unreadable WAR file : invalid END header (bad central directory offset) /mbp/tomcat6/apache-tomcat-6.0.24/webapps/cib.war
at org.apache.naming.resources.WARDirContext.setDocBase(WARDirContext.java:135)
at org.apache.catalina.core.StandardContext.resourcesStart(StandardContext.java:4086)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4255)
at org.apache.catalina.core.ContainerBase.addChildInternal(Con
出现情况：war项目放在Tomcat下Windows系统时启动正常，将war包ftp到AIX(或者Linux)下启动的时候出现此异常。
原因：ftp上传文件的时候，默认是以ASCII上传，对war文件有影响，到AIX的Tomcat下就不能启动了。。。
解决方法：将FTP的上传方式改为二进制上传。
编译异常：
The type org.springframework.dao.support.DaoSupport cannot be resolved. It is indirectly referenced from required .class files
出现情况：Dao类继承DaoSupport类(e.g. SqlMapClientDaoSupport or HibernateDaoSupport)的时候，编译出错
原因：Spring框架中此类的依赖库没有导入。
解决方法：将org.springframework.transaction-3.1.0.RELEASE.jar导入即可。
org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: Failed to import bean definitions from relative location [applicationContext.xml]
Offending resource: class path resource [resources/spring/applicationContext.xml]; nested exception is org.springframework.beans.factory.BeanDefinitionStoreException: Unexpected exception parsing XML document from class path resource [resources/spring/applicationContext.xml]; nested exception is java.lang.NoClassDefFoundError: org/aopalliance/intercept/MethodInterceptor
at org.springframework.beans.factory.parsing.FailFastProblemReporter.error(FailFastProblemReporter.java:68)
at org.springframework.beans.factory.parsing.ReaderContext.error(ReaderContext.java:85)
at org.springframework.beans.factory.parsing.ReaderContext.error(ReaderContext.java:76)
解决方法：缺少aopalliance.jar包，倒入即可
org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: Unable to locate Spring NamespaceHandler for XML schema namespace [http://www.springframework.org/schema/aop]
Offending resource: class path resource [resources/spring/applicationContext.xml]
原因：在xml中使用了 xmlns:aop="http://www.springframework.org/schema/aop" ，但是却没有倒入spring的aop.jar包
java.lang.NoClassDefFoundError: org/aspectj/weaver/reflect/ReflectionWorld$ReflectionWorldException
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Class.java:2427)
at java.lang.Class.getDeclaredMethods(Class.java:1791)
缺少aspectjweaver.jar
com.opensymphony.xwork2.inject.DependencyException: com.opensymphony.xwork2.inject.ContainerImpl$MissingDependencyException: No mapping found for dependency [type=com.opensymphony.xwork2.ObjectFactory, name='default'] in public void com.opensymphony.xwork2.config.providers.XmlConfigurationProvider.setObjectFactory(com.opensymphony.xwork2.ObjectFactory).
at com.opensymphony.xwork2.inject.ContainerImpl.addInjectorsForMembers(ContainerImpl.java:157)
查询了半天，看网上有人碰到过，但是没有解决，于是分析代码进行查询原因，原因就是配置文件struts配置文件没有找到，于是想到了修改的配置，经过查询代码发现了这个问题，就是如果你要是修改了config，以后所有的配置只会读取配置的文件，所以struts-spring.jar等插件都采用的default的配置，所以会出错，故修改config的配置，把default的文件全部添加上，然后再添加上自己的配置文件，本来可以采用Dispatcher的DEFAULT_CONFIGURATION_PATHS然后添加自己的配置文件就可以，但是发现这个变量是private的，所有只能把里面的内容全部拷贝出来，所以这个地方的扩展自定义功能也是没有太大意义的。
<param-name>config</param-name>
<param-value>
struts-default.xml,struts-plugin.xml,struts.xml
</param-value>
Caused by: java.lang.ClassNotFoundException: org.hibernate.annotations.common.reflection.ReflectionManager
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1680)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526)
这个问题在使用新版本的hibernate包的时候容易出现，需要加入另外一个hibernate包hibernate-commons-annotations-4.0.1.Final.jar
最好是把所有的hibernate中required文件夹下的包全部加进去就好了
Caused by: java.lang.NoClassDefFoundError: org/jboss/logging/BasicLogger
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)
at java.lang.ClassLoader.defineClass(ClassLoader.java:615)
如上面所示，少了required文件夹与日志相关的jboss－logging.jar
Unable to load configuration. - bean - jar:file:/F:/Web/homesite/jsp/struts/WEB-INF/lib/struts2-convention-plugin-2.1.6.jar!/struts-plugin.xml:30:119
at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:58)
at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:360)
at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:403)
at org.apache.struts2.dispatcher.FilterDispatcher.init(FilterDispatcher.java:190)
at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:275)
此error是由于Struts2引起的。Struts2较早版本各个包之间的依赖性不强，用到的时候随时添加都可以。
但是后面比较新的版本就不行了，必须把其必备包全部放在lib下面，否则就报上面的错误
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at com.opensymphony.xwork2.inject.ContainerImpl$MethodInjector.inject(ContainerImpl.java:295)
at com.opensymphony.xwork2.inject.ContainerImpl$ConstructorInjector.construct(ContainerImpl.java:431)
at com.opensymphony.xwork2.inject.ContainerBuilder$5.create(ContainerBuilder.java:207)
at com.opensymphony.xwork2.inject.Scope$2$1.create(Scope.java:51)
at com.opensymphony.xwork2.inject.ContainerBuilder$3.create(ContainerBuilder.java:93)
at com.opensymphony.xwork2.inject.ContainerBuilder$7.call(ContainerBuilder.java:487)
at com.opensymphony.xwork2.inject.ContainerBuilder$7.call(ContainerBuilder.java:484)
at com.opensymphony.xwork2.inject.ContainerImpl.callInContext(ContainerImpl.java:574)
at com.opensymphony.xwork2.inject.ContainerBuilder.create(ContainerBuilder.java:484)
at com.opensymphony.xwork2.config.impl.DefaultConfiguration.createBootstrapContainer(DefaultConfiguration.java:252)
at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:193)
at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:66)
at org.apache.struts2.dispatcher.Dispatcher.init_PreloadConfiguration(Dispatcher.java:380)
at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:424)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.opensymphony.xwork2.inject.ContainerImpl$MethodInjector.inject(ContainerImpl.java:293)
... 33 more
缺少javassist.jar
严重: Exception starting filter struts2Config
Unable to load configuration. - action - file:/WorkPlace/Site/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/imix/WEB-INF/classes/resources/struts/struts.xml:69:46
at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:437)
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:295)
at org.apache.catalina.core.ApplicationFilterConfig.setFilterDef(ApplicationFilterConfig.java:422)
at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:115)
at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4072)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4726)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1057)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:840)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1057)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:463)
at org.apache.catalina.core.StandardService.start(StandardService.java:525)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:754)
at org.apache.catalina.startup.Catalina.start(Catalina.java:595)
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)
如果你的struts.xml和applicationContext.xml配置正确，依然出现此问题，就是缺少Struts所依赖的一些包文件（struts2－spring－plugin.jar, commons类库）
javax.servlet.ServletException: Class org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter is not a Servlet
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:602)
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
java.lang.Thread.run(Unknown Source)
出现此问题是因为将Struts的StrutsPrepareAndExecuteFilter配置成了<servlet>，正确配置为<filter>过滤器（该类是个Filter，不是Servlet）
运行时异常
Exception in thread "main" java.lang.ClassCastException: com.sun.proxy.$Proxy0 cannot be cast to test.test.DaoImpl
at test.test.T.main(T.java:25)
出现此问题是因为使用JDK的代理(Proxy)时，没有使用接口或者返回时不是用接口强转的，例如以下代码：
DaoImpl di = (DaoImpl)new DaoProxy().bind(new DaoImpl()); // 应该用DaoImpl的接口来强转(JDK自带的Proxy只能动态代理实现接口的类，如果需要代理无接口的类需要使用cglib动态代理) di.print(); // 正确做法为： Dao di = (Dao)new DaoProxy().bind(new DaoImpl()); di.print();
Exception in thread "main" java.lang.IncompatibleClassChangeError: class net.sf.cglib.core.DebuggingClassWriter has interface org.objectweb.asm.ClassVisitor as super class
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at net.sf.cglib.core.DefaultGeneratorStrategy.getClassVisitor(DefaultGeneratorStrategy.java:30)
at net.sf.cglib.core.DefaultGeneratorStrategy.generate(DefaultGeneratorStrategy.java:24)
at net.sf.cglib.core.AbstractClassGenerator.create(AbstractClassGenerator.java:216)
at net.sf.cglib.core.KeyFactory$Generator.create(KeyFactory.java:144)
at net.sf.cglib.core.KeyFactory.create(KeyFactory.java:116)
at net.sf.cglib.core.KeyFactory.create(KeyFactory.java:108)
at net.sf.cglib.core.KeyFactory.create(KeyFactory.java:104)
at net.sf.cglib.proxy.Enhancer.<clinit>(Enhancer.java:69)
at test.test.DaoCglib.getInstance(DaoCglib.java:21)
at test.test.T.main(T.java:27)
版本冲突，报错java.lang.IncompatibleClassChangeError: class net.sf.cglib.core.DebuggingClassWriter has interface org.objectweb.asm.ClassVisitor as super class
使用cglib 2.2 可解决此问题,该版本中的DebuggingClassWriter的父类为ClassWriter
