Sometimes during the deployment of new applications in Tomcat you may see errors like ‘org.apache.catalina.core.StandardContext listenerStart’ in your startup log.

This may be caused due to many reasons (missing classes, including javax.servlet.* jars with your application, etc), but the reason is not displayed in the startup log.

But you can find out what is causing this error by adding logging.properties to your $TOMCAT_HOME/conf directory, with the following content:

org.apache.catalina.core.ContainerBase.[Catalina].level = DEBUG
org.apache.catalina.core.ContainerBase.[Catalina].handlers = java.util.logging.ConsoleHandler

After that you should be able to see the whole exception and figure out what is causing your application to fail.

Happy hacking!