如何在JPA / Hibernate应用程序(没有Spring)中配置连接池?

时间:2013-08-02 06:40:35

标签: java hibernate java-ee jpa-2.0 connection-pooling

的persistence.xml

    <properties>
        <property name='javax.persistence.jdbc.driver' value='org.postgresql.Driver' />
        <property name='javax.persistence.jdbc.url'
            value='jdbc:postgresql://192.168.19.66:5432/service1' />
        <property name='javax.persistence.jdbc.user' value='postgres' />
        <property name='javax.persistence.jdbc.password' value='root' />
        <property name='hibernate.dialect' value='org.hibernate.dialect.PostgreSQLDialect' />
        <property name='hibernate.connection.shutdown' value='true' />
        <property name='hibernate.hbm2ddl.auto' value='none' />
        <property name='hibernate.show_sql' value='false' />
        <property name='hibernate.format_sql' value='false' />
                    <!-- Connection Pooling -->
        <property name="hibernate.connection.provider_class"
            value="org.hibernate.service.jdbc.connections.internal.C3P0ConnectionProvider" />
        <property name="hibernate.c3p0.max_size" value="100" />
        <property name="hibernate.c3p0.min_size" value="5" />
        <property name="hibernate.c3p0.acquire_increment" value="5" />
        <property name="hibernate.c3p0.idle_test_period" value="500" />
        <property name="hibernate.c3p0.max_statements" value="50" />
        <property name="hibernate.c3p0.timeout" value="10000" />
    </properties>

异常

[C3P0PooledConnectionPoolManager[identityToken->1hge4qw8wh4gndjoawud4|b81be4]-AdminTaskTimer] DEBUG com.mchange.v2.async.ThreadPoolAsynchronousRunner - com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@5d1aef -- Running DeadlockDetector[Exiting. No pending tasks.]
[C3P0PooledConnectionPoolManager[identityToken->1hge4qw8wh4gndjoawud4|b81be4]-AdminTaskTimer] DEBUG com.mchange.v2.resourcepool.BasicResourcePool - Continuing acquisition series. pending_acquires [5],  attempts_remaining: 20
[C3P0PooledConnectionPoolManager[identityToken->1hge4qw8wh4gndjoawud4|b81be4]-AdminTaskTimer] DEBUG com.mchange.v2.async.ThreadPoolAsynchronousRunner - com.mchange.v2.async.ThreadPoolAsynchronousRunner@b66600: Adding task to queue -- com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask@934847
[C3P0PooledConnectionPoolManager[identityToken->1hge4qw8wh4gndjoawud4|b81be4]-HelperThread-#0] DEBUG com.mchange.v2.resourcepool.BasicResourcePool - An exception occurred while acquiring a poolable resource. Will retry.
java.sql.SQLException: No suitable driver
    at java.sql.DriverManager.getDriver(DriverManager.java:264)
    at com.mchange.v2.c3p0.DriverManagerDataSource.driver(DriverManagerDataSource.java:240)
    at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:146)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:195)
    at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:184)
    at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:200)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1086)
    at com.mchange.v2.resourcepool.BasicResourcePool.doAcquireAndDecrementPendingAcquiresWithinLockOnSuccess(BasicResourcePool.java:1073)
    at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:44)
    at com.mchange.v2.resourcepool.BasicResourcePool$ScatteredAcquireTask.run(BasicResourcePool.java:1810)
    at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:648)

获取异常 java.sql.SQLException:没有合适的驱动程序

当我查看源代码时,它正在寻找属性“hibernate.connection.driver_class”。我已经在“javax.persistence.jdbc.driver”中提到了驱动程序类。

我认为我没有正确配置连接池。该应用程序使用的是hibernate 4.1.11(没有spring),JPA2,Postgresql 9.1。没有hibernate.cfg.xml。

问题

  • 在Hibernate / JPA应用程序中配置连接池的方法是什么。
  • 我已经在javax.persistence.jdbc.driver中提供了?如果我提供hibernate.connection.driver_class属性,连接池和JPA连接创建的连接是相同还是不同?

注意

  • Postgresql驱动程序在classpath中。
  • 如果我删除<!-- Connection Pooling -->之后的行,则会运行。但是如果我在<!-- Connection Pooling -->之后为连接池添加行,我就会遇到此异常。

2 个答案:

答案 0 :(得分:0)

回到过去,您必须使用Class.forName(org.postgresql.Driver.class)构造加载相应的驱动程序类。使用JDBC 4.0驱动程序不再需要 - 但您可以尝试一下。

或者,尝试使用-Djdbc.drivers=org.postgresql.Driver启动应用程序,它与Class.forName代码段几乎相同,但不要求您对驱动程序类进行硬编码。希望它有所帮助。

答案 1 :(得分:0)

从答案

https://stackoverflow.com/a/10899364/112500

我能够解决问题。

将此行添加到c3p0-config.xml

之后
<property name="driverClass">org.postgresql.Driver</property>