Tomcat 7 (when a servlet project) is included is n

Question

Tomcat 7 is not starting when a web application(with a servlet) is attempted to run.The server works well when i only have a html page.But when i try to add a servlet and add it to tomcat.Then the server does not start and gives an error saying "Tomcat 7 didn't start in 45 seconds". I increased the timeout but nothing happened.Please help me solve this problem

The Console says :

"23 Jan, 2012 1:43:44 PM org.apache.catalina.core.AprLifecycleListener init
INFO: The APR based Apache Tomcat Native library which allows optimal performance in                  production environments was not found on the java.library.path: C:\Program Files (x86)\Java\jdk1.7.0\bin;.;C:\Windows\Sun\Java\bin;C:\Windows\system32;C:\Windows;C:/Program Files/Java/jdk1.6.0_23/jre/bin/server;C:/Program Files/Java/jdk1.6.0_23/jre/bin;C:/Program Files/Java/jdk1.6.0_23/jre/lib/amd64;C:\Program Files (x86)\Java\jdk1.7.0\jre\bin;F:\SOFTWARES\Eclipse Indigo\eclipse;
23 Jan, 2012 1:43:44 PM org.apache.tomcat.util.digester.SetPropertiesRule begin
WARNING: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property     'source' to 'org.eclipse.jst.jee.server:Basic' did not find a matching property.
23 Jan, 2012 1:43:44 PM org.apache.coyote.AbstractProtocol init
INFO: Initializing ProtocolHandler ["http-bio-80"]
23 Jan, 2012 1:43:44 PM org.apache.coyote.AbstractProtocol init
INFO: Initializing ProtocolHandler ["ajp-bio-9999"]
23 Jan, 2012 1:43:44 PM org.apache.catalina.startup.Catalina load
INFO: Initialization processed in 717 ms
23 Jan, 2012 1:43:44 PM org.apache.catalina.core.StandardService startInternal
INFO: Starting service Catalina
23 Jan, 2012 1:43:44 PM org.apache.catalina.core.StandardEngine startInternal
INFO: Starting Servlet Engine: Apache Tomcat/7.0.23
23 Jan, 2012 1:43:45 PM org.apache.catalina.core.ContainerBase startInternal
SEVERE: A child container failed during start
java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component     [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/Basic]]
at java.util.concurrent.FutureTask$Sync.innerGet(FutureTask.java:252)
at java.util.concurrent.FutureTask.get(FutureTask.java:111)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1100)
at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:782)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1525)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1515)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:674)
    Caused by: org.apache.catalina.LifecycleException: Failed to start component     [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/Basic]]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
    ... 7 more
    Caused by: java.lang.UnsupportedClassVersionError: Simple : Unsupported major.minor version 51.0 (unable to load class Simple)
at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:2827)
at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:1160)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1655)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1533)
at org.apache.catalina.startup.WebAnnotationSet.loadApplicationServletAnnotations(WebAnnotationSet.java:108)
at org.apache.catalina.startup.WebAnnotationSet.loadApplicationAnnotations(WebAnnotationSet.java:58)
at org.apache.catalina.startup.ContextConfig.applicationAnnotationsConfig(ContextConfig.java:338)
at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:831)
at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:302)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5148)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
... 7 more
23 Jan, 2012 1:43:45 PM org.apache.catalina.core.ContainerBase startInternal
SEVERE: A child container failed during start
java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to     start component [StandardEngine[Catalina].StandardHost[localhost]]
at java.util.concurrent.FutureTask$Sync.innerGet(FutureTask.java:252)
at java.util.concurrent.FutureTask.get(FutureTask.java:111)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1100)
at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:291)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.StandardService.startInternal(StandardService.java:443)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:727)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.startup.Catalina.start(Catalina.java:624)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:623)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:322)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:450)
Caused by: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1525)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1515)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:674)
Caused by: org.apache.catalina.LifecycleException: A child container failed during start
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:1108)
at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:782)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
... 7 more
23 Jan, 2012 1:43:45 PM org.apache.catalina.startup.Catalina start
SEVERE: Catalina.start: 
org.apache.catalina.LifecycleException: Failed to start component [StandardServer[8000]]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
at org.apache.catalina.startup.Catalina.start(Catalina.java:624)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:623)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:322)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:450)
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:727)
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:1108)
at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:291)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
... 11 more
23 Jan, 2012 1:43:45 PM org.apache.catalina.startup.Catalina start
INFO: Server startup in 313 ms "    '

Answer 1

Check the configuration in the file servers.xml in the Package Explorer under Servers in Eclipse. When you open this file in Design-mode, you can see the different Contexts-configs. For you start there should be an entry. Check this Context entry: the docBase, path and source should refer to your project.

Answer 2

If you just copied the error message of the cause of the exception into Google, you would have found the problem. "Unsupported major.minor version 51.0" means that you compiled the classes with JDK7, but try to deploy and run it with a previous version of the JDK or JRE. Start your tomcat with JDK7, or change the JDK you're using to compile your classes.

Side note: your class seems to be named Simple and to be in the default package. This ie a bad practice that will cause all sorts of problems. Always put your classes in a package.