com.mchange.v2.resourcepool.ResourcePoolException: Attempted to use a closed or broken resource pool
解决这个异常需要修改设置成如下：
<property name="acquireRetryAttempts">
<value>30</value>
</property>
<property name="acquireRetryDelay">
<value>100</value>
</property>
<property name="breakAfterAcquireFailure">
<value>false</value>
</property>
Default: 30
Defines how many times c3p0 will try to acquire a new Connection from the database before giving up. If this value is less than or equal to zero, c3p0 will keep trying to fetch a Connection indefinitely
- acquireRetryDelay
Default: 1000
Milliseconds, time c3p0 will wait between acquire attempts.
- breakAfterAcquireFailure
Default: false
If true, a pooled DataSource will declare itself broken and be permanently closeed if a Connection cannot be obtained from the database after making acquireRetryAttempts to acquire one. If false, failure to obtain a Connection will cause all Threads waiting for the pool to acquire a Connection to throw an Exception, but the DataSource will remain valid, and will attempt to acquire again following a call to getConnection().