警告: A C3P0Registry mbean is already registered. This probably means that an application...

问题描述：

六月 23, 2017 9:16:59 下午 com.mchange.v2.log.MLog <clinit>
信息: MLog clients using java 1.4+ standard logging.
六月 23, 2017 9:16:59 下午 com.mchange.v2.c3p0.C3P0Registry banner
信息: Initializing c3p0-0.9.2-pre1 [built 27-May-2010 01:00:49 -0400; debug? true; trace: 10]
六月 23, 2017 9:16:59 下午 com.mchange.v2.c3p0.management.ActiveManagementCoordinator 
attemptManageC3P0Registry
警告: A C3P0Registry mbean is already registered. 
This probably means that an application using c3p0 was undeployed, 
but not all PooledDataSources were closed prior to undeployment. 
This may lead to resource leaks over time. Please take care to close all PooledDataSources.

问题原因：

同一个web容器下部署了多个使用c3p0的项目