Java 网络故障后重新建立数据库连接-休眠

各位好,， 我正在使用hibernate ORM和oracle数据库。我的cfg文件具有以下属性：

    <property name="connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
    <property name="connection.url">jdbc:oracle:thin:@url</property>
    <property name="connection.username">username</property>
    <property name="connection.password">pasword</property>
    <property name="dialect">org.hibernate.dialect.Oracle9Dialect</property>                

    <property name="hibernate.c3p0.min_size">5</property>
    <property name="hibernate.c3p0.max_size">20</property>
    <property name="hibernate.c3p0.timeout">300</property>
    <property name="hibernate.c3p0.max_statements">50</property>
    <property name="hibernate.c3p0.idle_test_period">3000</property>    
    <property name="hibernate.c3p0.acquire_increment">3</property>

---

有没有办法重新建立连接？

如我所见，您已指定何时测试连接，但尚未指定如何测试连接。读一下。我想您应该只添加

preferredTestQuery

，通常类似于

select1 FROM DUAL

。

---

另请阅读此处

您需要配置数据库连接池-而不是休眠。请尝试设置

idleConnectionTestPeriod

和适当的

preferredTestQuery

，例如，

从dual

中选择1

有关更多信息，请参阅。如果在

WEB-INF/classes

中创建

c3p0.properties

文件，您将获得最大的控制权，但您需要确保不要在

hibernate.cfg.xml

中覆盖这些属性

我编写了c3p0-config.xml，就像

<c3p0-config>
<default-config>
<!-- Configuring Connection     Testing -->
<!-- property name="automaticTestTable">TEST_EMS_HIBERNATE_CONN</property -->
<property name="checkoutTimeout">0</property>
<property name="testConnectionOnCheckout">true</property>
<property name="testConnectionOnCheckin">false</property>
<property name="preferredTestQuery">SELECT 1 from dual</property>
<!-- Configuring Recovery From Database Outages -->
<property name="acquireRetryAttempts">0</property>
<property name="acquireRetryDelay">1000</property>
<property name="breakAfterAcquireFailure">false</property>
<!-- Configuring to     Debug and Workaround Broken     Client Apps     -->
<property name="unreturnedConnectionTimeout">1800</property>
<property name="debugUnreturnedConnectionStackTraces">true</property>
</default-config>

0
真的
假的
从双重选择中选择1
0
1000
假的
1800
真的

以及系统属性，如：

C3P0\u SYS\u PROPS=“-Dcom.mchange.v2.C3P0.cfg.xml=/C3P0-config.xml-Dcom.mchange.v2.log.MLog=com.mchange.v2.log.FallbackMLog-Dcom.mchange.v2.log.FallbackMLog.DE
故障\切断\级别=警告“

<c3p0-config>
<default-config>
<!-- Configuring Connection     Testing -->
<!-- property name="automaticTestTable">TEST_EMS_HIBERNATE_CONN</property -->
<property name="checkoutTimeout">0</property>
<property name="testConnectionOnCheckout">true</property>
<property name="testConnectionOnCheckin">false</property>
<property name="preferredTestQuery">SELECT 1 from dual</property>
<!-- Configuring Recovery From Database Outages -->
<property name="acquireRetryAttempts">0</property>
<property name="acquireRetryDelay">1000</property>
<property name="breakAfterAcquireFailure">false</property>
<!-- Configuring to     Debug and Workaround Broken     Client Apps     -->
<property name="unreturnedConnectionTimeout">1800</property>
<property name="debugUnreturnedConnectionStackTraces">true</property>
</default-config>