Caused by: com.mchange.v2.resourcepool.TimeoutException: A client timed out while waiting to acquire a resource from com.mchange.v2.resourcepool.BasicResourcePool@1483de4 -- timeout at awaitAvailable(

Caused by: com.mchange.v2.resourcepool.TimeoutException: A client timed out while waiting to acquire a resource from com.mchange.v2.resourcepool.BasicResourcePool@1483de4 -- timeout at awaitAvailable()

把spring-dao.xml中

<property name="maxPoolSize" value="30"/>
改成

<property name="maxPoolSize" value="40"/>
运行正常，不抛出异常
再重新改回

<property name="maxPoolSize" value="30"/>
运行正常，没有异常

有可能是多运行几次，就不会有异常了？不能解决

解决办法
将url加上autoReconnect=true&rewriteBatchedStatements=TRUE

jdbc.url=jdbc:mysql://127.0.0.1:3306/seckill?useUnicode=true&characterEncoding=utf8&autoReconnect=true&rewriteBatchedStatements=TRUE