当你启动tomcat的时候如果报类似下面的错误：
WARNING: [SetContextPropertiesRule]{Context} Setting property 'source' to 'org.eclipse.jst.j2ee.server:CongressApp' did not find a matching property. May 13, 2014 1:35:26 PM org.apache.catalina.core.StandardContext listenerStart SEVERE: Error configuring application listener of class org.apache.catalina.deploy.ApplicationListener@bdeab java.lang.ClassNotFoundException: com.iss.congress.core.util.CongressContextListener at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559) at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:527) at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:509) at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:137) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4854) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5434) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633) at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:656) at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1635) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334) at java.util.concurrent.FutureTask.run(FutureTask.java:166) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:722)
May 13, 2014 1:35:26 PM org.apache.catalina.core.StandardContext listenerStart SEVERE: Error configuring application listener of class org.apache.catalina.deploy.ApplicationListener@6a5b20 java.lang.ClassNotFoundException: com.iss.congress.core.util.CongressHttpSessionListener at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559) at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:527) at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:509) at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:137) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4854) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5434) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633) at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:656) at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1635) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334) at java.util.concurrent.FutureTask.run(FutureTask.java:166) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:722)
May 13, 2014 1:35:26 PM org.apache.catalina.core.StandardContext listenerStart SEVERE: Error configuring application listener of class org.apache.catalina.deploy.ApplicationListener@1bacb12 java.lang.ClassNotFoundException: com.iss.congress.core.util.HibernateListener at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559) at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:527) at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:509) at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:137) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4854) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5434) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633) at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:656) at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1635) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334) at java.util.concurrent.FutureTask.run(FutureTask.java:166) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:722)
恭喜你，我这里可能帮到你，总结：
1、请把tomcat配置中serve modules without publishing的勾去掉
2、如果是源码，那么你的项目确实没有这个Listener .java
3、如果引用了jar包，那可能jar包没这个Listener .class，如果有请查看你.classpath有没有这个jar包，没有就加入