Q:

Starting tomcat server with error

when i starting tomcat server
I got this error 
INFO: Server startup in 1751 ms
20 mai 2014 10:42:47 org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc
GRAVE: The web application [/servlet] registered the JDBC driver [org.postgresql.Driver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered.
20 mai 2014 10:42:47 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
GRAVE: The web application [/servlet] appears to have started a thread named [Thread-4] but has failed to stop it. This is very likely to create a memory leak.
20 mai 2014 10:42:47 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
GRAVE: The web application [/servlet] appears to have started a thread named [CronTriggers_Worker-1] but has failed to stop it. This is very likely to create a memory leak.
20 mai 2014 10:42:47 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
GRAVE: The web application [/servlet] appears to have started a thread named [CronTriggers_Worker-2] but has failed to stop it. This is very likely to create a memory leak.

can you help me please

A:

Check whether you have created any static connection objects. Static object tend to live in the server heap even when the application is stopped.

