title: Eclipse tomcat error: Document base does not exist or is not a readable directory
body: <pre><code>13-dic-2011 17.00.36 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: /usr/lib/jvm/java-6-openjdk/jre/lib/amd64/server:/usr/lib/jvm/java-6-openjdk/jre/lib/amd64:/usr/lib/jvm/java-6-openjdk/jre/../lib/amd64:/usr/java/packages/lib/amd64:/usr/lib/jni:/lib:/usr/lib
  13-dic-2011 17.00.36 org.apache.tomcat.util.digester.SetPropertiesRule begin
  AVVERTENZA: [SetPropertiesRule]{Server/Service/Engine/Host/Context} Setting property 'source' to 'org.eclipse.jst.jee.server:Preventivi' did not find a matching property.
  13-dic-2011 17.00.36 org.apache.coyote.AbstractProtocol init
  INFO: Initializing ProtocolHandler ["http-bio-8080"]
  13-dic-2011 17.00.36 org.apache.coyote.AbstractProtocol init
  INFO: Initializing ProtocolHandler ["http-bio-8443"]
  13-dic-2011 17.00.37 org.apache.coyote.AbstractProtocol init
  INFO: Initializing ProtocolHandler ["ajp-bio-8009"]
  13-dic-2011 17.00.37 org.apache.catalina.startup.Catalina load
  INFO: Initialization processed in 983 ms
  13-dic-2011 17.00.37 org.apache.catalina.core.StandardService startInternal
  INFO: Starting service Catalina
  13-dic-2011 17.00.37 org.apache.catalina.core.StandardEngine startInternal
  INFO: Starting Servlet Engine: Apache Tomcat/7.0.23
  13-dic-2011 17.00.37 org.apache.catalina.core.StandardContext resourcesStart
  GRAVE: Error starting static Resources
  java.lang.IllegalArgumentException: Document base /home/claudio/workspace/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/Preventivi does not exist or is not a readable directory
      at org.apache.naming.resources.FileDirContext.setDocBase(FileDirContext.java:140)
      at org.apache.catalina.core.StandardContext.resourcesStart(StandardContext.java:4880)
      at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5060)
      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:636)
  13-dic-2011 17.00.37 org.apache.catalina.core.StandardContext startInternal
  GRAVE: Error in resourceStart()
  13-dic-2011 17.00.37 org.apache.catalina.core.StandardContext startInternal
  GRAVE: Error getConfigured
  13-dic-2011 17.00.37 org.apache.catalina.core.StandardContext startInternal
  GRAVE: Context [/Preventivi] startup failed due to previous errors
  13-dic-2011 17.00.37 org.apache.coyote.AbstractProtocol start
  INFO: Starting ProtocolHandler ["http-bio-8080"]
  13-dic-2011 17.00.37 org.apache.coyote.AbstractProtocol start
  INFO: Starting ProtocolHandler ["http-bio-8443"]
  13-dic-2011 17.00.37 org.apache.coyote.AbstractProtocol start
  INFO: Starting ProtocolHandler ["ajp-bio-8009"]
  13-dic-2011 17.00.37 org.apache.catalina.startup.Catalina start
  INFO: Server startup in 319 ms
  </code></pre>
  
  <p>I've run my webapp project in Eclipse, but today I received the message in console.
  Tomcat return me a 404 page error. Maybe the problem is that the folder where I would write doesn't exist. Where is the trick?</p>