我有一个使用Spring JPA和休眠连接到mysql数据库的Web应用程序。如果与数据库的连接由于任何原因而断开,我想捕获该异常,以便我可以暂停处理,然后永久轮询该连接,直到它恢复。
休眠/春季 jpa 中是否有任何设置来应对此问题?
应用程序上下文.xml:
<bean id="dataSource"
class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName">
<value>com.mysql.jdbc.Driver</value>
</property>
<property name="url">
<value>jdbc:mysql:${db.loc}</value>
</property>
<property name="username">
<value>${db.username}</value>
</property>
<property name="password">
<value>${db.password}</value>
</property>
</bean>
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource" />
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter" />
</property>
<property name="packagesToScan" value="com.georgelung.template" />
<property name="jpaProperties">
<props>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.format_sql">false</prop>
<prop key="hibernate.hbm2ddl.auto">update</prop>
</props>
</property>
</bean>
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
模板存储库类
@Repository
public interface TemplateRepository extends CrudRepository<TestEntity, Long> {
}
为什么要捕获数据库的连接丢失并尝试在休眠时手动重新连接 提供开箱即用的解决方案
在休眠配置中添加以下代码应该可以解决您的问题
<prop key="hibernate.connection.autoReconnect">true</prop>
<prop key="hibernate.connection.autoReconnectForPools">true</prop>
您需要创建一个这样的getConnection
方法,以确保在尝试连接到数据库之前具有有效的连接:
private Connection getConnection() {
Connection connection = null;
try {
// This should return a NEW connection!
Connection connection = dataSource.getConnection();
} catch (Exception e) {
// here you got the no connection found exception!
System.err.println("Connection failed: " + e);
}
return connection;
}