JDBC MySQL - 連接已關閉

Question

我有一個Web應用程序。我使用JPA（Hibernate作爲供應商），該應用程序在glassfish服務器上運行。使用該應用程序（包括檢索和保存實體到數據庫操作）幾分鐘後我得到這個錯誤：

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is javax.persistence.PersistenceException: org.hibernate.exception.GenericJDBCException: Could not open connection 
root cause 

javax.persistence.PersistenceException: org.hibernate.exception.GenericJDBCException: Could not open connection 
root cause 

org.hibernate.exception.GenericJDBCException: Could not open connection 
root cause 

java.sql.SQLException: Error in allocating a connection. Cause: java.lang.RuntimeException: Got exception during XAResource.start: 
root cause 

javax.resource.spi.ResourceAllocationException: Error in allocating a connection. Cause: java.lang.RuntimeException: Got exception during XAResource.start: 
root cause 

com.sun.appserv.connectors.internal.api.PoolingException: java.lang.RuntimeException: Got exception during XAResource.start: 
root cause 

com.sun.appserv.connectors.internal.api.PoolingException: java.lang.RuntimeException: Got exception during XAResource.start: 
root cause 

java.lang.RuntimeException: Got exception during XAResource.start: 
root cause 

javax.transaction.xa.XAException: com.sun.appserv.connectors.internal.api.PoolingException: javax.resource.spi.LocalTransactionException: No operations allowed after connection closed. 

我使用JTA事務管理器。我的服務層中的每個功能都有@Transactional註釋。這是我的persistence.xml：

<?xml version="1.0" encoding="UTF-8"?> 
<persistence xmlns="http://java.sun.com/xml/ns/persistence" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd" 
    version="2.0"> 
    <persistence-unit name="myPU" transaction-type="JTA"> 

     <provider>org.hibernate.ejb.HibernatePersistence</provider> 
     <jta-data-source>jdbc/myDataSource</jta-data-source> 

     <class>org.company.entities.User</class> 
      <!-- OTHER CLASSES --> 

     <exclude-unlisted-classes /> 

     <properties> 
      <property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5Dialect" /> 
      <property name="hibernate.transaction.flush_before_completion" value="true" /> 
      <property name="hibernate.show_sql" value="false" /> 
      <property name="hibernate.connection.release_mode" value="auto"/> 
      <property name="hibernate.current_session_context_class" value="jta"/> 
      <property name="hibernate.transaction.auto_close_session" value="true"/> 
<!--    <property name="hibernate.transaction.flush_before_completion" value="true"/> --> 
<!--    <property name="hibernate.transaction.factory_class" value="org.hibernate.transaction.JTATransactionFactory"/> --> 
     </properties> 

    </persistence-unit> 
</persistence> 

我使用這個MySQL連接器：mysql-connector-java-5.1.22-bin.jar 爲什麼會出現這個錯誤？我或JPA在哪裏關閉連接？

編輯：刪除類「BaseEntityDAO」的細節 - 不相關。我的數據源通過在GlassFish的管理控制檯配置： 在JDBC連接池：

• 資源類型：javax.sql.DataSource的
• DataSource類名稱：com.mysql.jdbc.jdbc2。可選.MysqlDataSource
• 使用glassfish的默認池設置 - 不知道它是否重要，但其中一個默認設置是「空閒超時」，其默認值爲300秒。
• 在附加屬性我的hve以下屬性：端口號，的databaseName中ServerName，用戶，密碼

在JDBC資源：

• JNDI名稱：JDBC/myDataSource
• 普爾名稱：上述JDBC連接池的池名稱

這是我的彈簧配置：

<jee:jndi-lookup id="entityManagerFactory" jndi-name="persistence/myPersistenceUnit" /> 

<bean 
    class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor"> 
    <property name="persistenceUnits"> 
     <map> 
      <entry key="myPersistenceUnit" value="persistence/myPersistenceUnit" /> 
     </map> 
    </property> 
</bean> 

<tx:annotation-driven transaction-manager="transactionManager" /> 
<bean id="transactionManager" class="org.springframework.transaction.jta.JtaTransactionManager" /> 

<jee:jndi-lookup id="dataSource" jndi-name="jdbc/myDataSource" /> 

<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate"> 
    <constructor-arg ref="dataSource" /> 
</bean> 

Answer 1

你可以得到與C3P0嘗試與此配置：

<property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property> 
<property name="c3p0.testConnectionOnCheckout">false</property> 
<property name="c3p0.min_size">2</property> 
<property name="c3p0.max_size">10</property> 
<property name="c3p0.timeout">300</property> 
<property name="c3p0.max_statements">50</property> 
<property name="c3p0.idleTestPeriod">300</property> 

我使用在許多項目中此配置，因爲多年。