java - 连接关闭后不允许进行任何操作。连接已被驱动程序隐式关闭。 C3P0

Question

我正在尝试使用 c3p0 连接池上传图像(一张一张)，但我的 jdbc 类型 4 驱动程序(连接到 mysql)一直关闭连接。我看到mysql的配置中最大超时设置为300秒。这是我的持久性 xml 如何使用 c3p0。

<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
    scope="singleton" destroy-method="close">
    <property name="driverClass" value="...." />
    <property name="jdbcUrl" value="...." />
    <property name="user" value="....." />
    <property name="password" value="...." />
    <property name="initialPoolSize" value="10" />
    <property name="minPoolSize" value="5" />
    <property name="maxPoolSize" value="20" />
    <property name="maxIdleTime" value="5" />
    <property name="autoCommitOnClose" value="false" />
</bean>

有人能解释一下究竟是什么导致驱动程序隐式关闭连接。另外，我该如何解决这个问题？

这是我收到的错误信息:

19:01:45,504  WARN NewPooledConnection:486 - [c3p0] A PooledConnection that has already signalled a Connection error is still in use!

19:01:45,505  WARN NewPooledConnection:487 - [c3p0] Another error has occurred [ 

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed.Connection was implicitly closed by the driver. ] which will not be reported to listeners!

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed.Connection was implicitly closed by the driver.

Answer 1

你能把这个改成

<property name="maxIdleTime" value="0" />  //0 = never expire