Tomcat – Version application parameter in tomcat’s manager

Those are the options for your JVM. to get the definitive list for the version you are running you can type java -h for the standard options and java -X for the non-standard options "the -X[X] options

Quick summary: there are several conditions (like changing the war file, deleting the webapp or replacing it with new content) under which tomcat will undeploy the context including removing the context file.

Details: Whether tomcat does or doesn't do autoDeployment (means checking for changes in your .xml descriptor as well as checking changes in the webapp directory) is driven by:

1. server.xml localted in $CATALINA_HOME/conf/server.xml section:

   <Host name="localhost" appBase="webapps" unpackWARs="true" autoDeploy="true" xmlValidation="false" xmlNamespaceAware="false">

2. You can also set this property in your context file overloading the value

Quoting the doc for cases when autoDeploy=true may cause removal of your context file:

• Deleting a WAR file will trigger an undeploy of the application with the removal of any associated expanded directory, context file and work directory.
• Deleting a directory will trigger an undeploy of the application with the removal of any associated context file and work directory.
• Updating a WAR file will trigger an undeploy of the application with the removal of any associated expanded directory, context file and work directory.
• Updating a directory (not the directory contents) will trigger an undeploy of the application with the removal of any associated context file and work directory.

Exhaustive details: http://tomcat.apache.org/tomcat-6.0-doc/config/host.html#Automatic%20Application%20Deployment