Tomcat部署项目时出错java.lang.IllegalStateException: ContainerBase.addChild: start:org.apache.catalina.LifecycleException: Failed to start component[StandardEngine[Catalina].StandardHost[localhost].StandardContext[/项目名]]
一个非常easy的项目。没有出现编译错误，从Eclipse中用Tomcat v7.0 server启动出现下面错误，貌似不是项目本身的问题（如由于库没有导入）。
六月 10, 2015 2:02:50 下午 org.apache.catalina.startup.Catalina start
严重: The required Server component failed to start so Tomcat is unable to start.
org.apache.catalina.LifecycleException: Failed to start component [StandardServer[8005]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
at org.apache.catalina.startup.Catalina.start(Catalina.java:689)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:321)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:455)
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardService[Catalina]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:739)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
… 7 more
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
at org.apache.catalina.core.StandardService.startInternal(StandardService.java:443)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
… 9 more
Caused by: org.apache.catalina.LifecycleException: A child container failed during start
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1131)
at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:300)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
… 11 more
六月 10, 2015 2:02:50 下午 org.apache.coyote.AbstractProtocol pause
信息: Pausing ProtocolHandler [“http-bio-8080”]
六月 10, 2015 2:02:50 下午 org.apache.coyote.AbstractProtocol pause
信息: Pausing ProtocolHandler [“ajp-bio-8009”]
六月 10, 2015 2:02:50 下午 org.apache.catalina.core.StandardService stopInternal
信息: Stopping service Catalina
六月 10, 2015 2:02:50 下午 org.apache.coyote.AbstractProtocol destroy
信息: Destroying ProtocolHandler [“http-bio-8080”]
六月 10, 2015 2:02:50 下午 org.apache.coyote.AbstractProtocol destroy
信息: Destroying ProtocolHandler [“ajp-bio-8009”]
把项目部署到tomcat文件夹下，用命令行启动。报下面错误。 
所以能够肯定得是是Tomcat容器在载入我们servlet的时候出现的问题。所以重点检查web.xml文件是否有问题：servlet是否都定义了，mapping映射是否定义正确….最后发现问题的本源在于servlet-name上下没有相应 