严重: The web application [] registered the JDBC driver 错误

近日发现启动tomcat的时候报如下警告:

2014-9-16 10:25:26 org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc
严重: The web application [] registered the JDBC driver [com.mysql.jdbc.Driver] but failed
to unregister it when the web application was stopped. To prevent a memory leak, the JDBC
Driver has been forcibly unregistered.
2014-9-16 10:25:26 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
严重: The web application [] appears to have started a thread named [Timer-0] but has
failed to stop it. This is very likely to create a memory leak.

原因:

使用killall 或者 kill -9直接杀死java进程,导致相关内存没有及时释放.

解决:

　　使用stop.sh来停止tomcat.