DEBUG -- CLOSE BY CLIENT STACK TRACE

Indeed, there is nothing to worry about.
Just odd log statements sprinkled throughout the C3P0 codebase.
Raise the loglevel to INFO and these statemens will not appear anymore.

CLOSE BY CLIENT STACK TRACE是C3P0代码里多日志语句抛出来的，调整日志级别为INFO就可以解决；