java - 已达到 MaxOpenPreparedStatements 限制

Question

仅在应用程序运行几天后，我的代码中的某些数据库更新才会出现此异常。有些请求通过了，有些(相同的java代码)失败了。

java.sql.SQLException: MaxOpenPreparedStatements limit reached
       at org.apache.commons.dbcp.PoolingConnection.prepareStatement(PoolingConnection.java:109)
       at org.apache.commons.dbcp.DelegatingConnection.prepareStatement(DelegatingConnection.java:281)
       at org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper.prepareStatement(PoolingDataSource.java:313)
       at com.prog.C.f(C.java:967)
       at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:885)
       at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
       at java.lang.Thread.run(Thread.java:619)
Caused by: java.util.NoSuchElementException
       at org.apache.commons.pool.impl.GenericKeyedObjectPool.borrowObject(GenericKeyedObjectPool.java:808)
       at org.apache.commons.dbcp.PoolingConnection.prepareStatement(PoolingConnection.java:107)
       ... 15 more

数据源配置:

<bean id="DataSource" class="org.apache.commons.dbcp.BasicDataSource"
          destroy-method="close" lazy-init="true" scope="singleton">
        <property name="driverClassName" value="${jdbc.driver.class}"/>
        <property name="url" value="${jdbc.url}"/>
        <property name="username" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
        <property name="poolPreparedStatements" value="true"/>
        <property name="maxOpenPreparedStatements" value="20"/>
    </bean>

始终有可用的连接。我该如何修复它？谢谢。

Answer 1

这意味着您可能没有正确关闭资源。您应该在创建它们的方法范围内的finally block 中执行此操作。