Имеет ли это значение dbcp Exception?

Question

Я использую пружинный 3.05 + MySQL, после выполнения программы, я нашел много исключений из журнала:

books.log.6- 09:24:45 Closing JPA EntityManager -org.springframework.orm.jpa.EntityManagerFactoryUtils 
books.log.6- 09:24:45 about to close PreparedStatement (open PreparedStatements: 1, globally: 1) -org.hibernate.jdbc.AbstractBatcher 
books.log.6- 09:24:45 aggressively releasing JDBC connection -org.hibernate.jdbc.ConnectionManager 
books.log.6- 09:24:45 releasing JDBC connection [ (open PreparedStatements: 0, globally: 0) (open ResultSets: 0, globally: 0)] -org.hibernate.jdbc.ConnectionManager 
books.log.6- 09:24:45 Cannot release connection [???] -org.hibernate.util.JDBCExceptionReporter 
books.log.6: java.sql.SQLException: Already closed. 
books.log.6- at org.apache.commons.dbcp.PoolableConnection.close(PoolableConnection.java:114) 
books.log.6- at org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper.close(PoolingDataSource.java:191) 
books.log.6- at org.hibernate.connection.DatasourceConnectionProvider.closeConnection(DatasourceConnectionProvider.java:97) 
books.log.6- at org.hibernate.jdbc.ConnectionManager.closeConnection(ConnectionManager.java:474) 
books.log.6- at org.hibernate.jdbc.ConnectionManager.aggressiveRelease(ConnectionManager.java:429) 
books.log.6- at org.hibernate.jdbc.ConnectionManager.afterStatement(ConnectionManager.java:304) 
books.log.6- at org.hibernate.jdbc.AbstractBatcher.closePreparedStatement(AbstractBatcher.java:572) 
books.log.6- at org.hibernate.jdbc.AbstractBatcher.closeStatement(AbstractBatcher.java:291) 
books.log.6- at org.hibernate.jdbc.AbstractBatcher.closeQueryStatement(AbstractBatcher.java:307) 
books.log.6- at org.hibernate.jdbc.AbstractBatcher.closeQueryStatement(AbstractBatcher.java:234) 
books.log.6- at org.hibernate.loader.Loader.getResultSet(Loader.java:1967) 
books.log.6- at org.hibernate.loader.Loader.doQuery(Loader.java:802) 
books.log.6- at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:274) 
books.log.6- at org.hibernate.loader.Loader.doList(Loader.java:2533) 
books.log.6- at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2276) 
books.log.6- at org.hibernate.loader.Loader.list(Loader.java:2271) 
books.log.6- at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:452) 
books.log.6- at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:363) 
books.log.6- at org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196) 
books.log.6- at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1268) 
books.log.6- at org.hibernate.impl.QueryImpl.list(QueryImpl.java:102) 
books.log.6- at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:246) 
books.log.6- at com.tekelec.books.domain.BookInfo.findAllBooks_aroundBody4(BookInfo.java:238) 
books.log.6- at com.tekelec.books.domain.BookInfo.findAllBooks(BookInfo.java:1) 
books.log.6- at com.tekelec.books.web.BooksController.getBooks(BooksController.java:37) 
books.log.6- at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
books.log.6- at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) 
books.log.6- at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
books.log.6- at java.lang.reflect.Method.invoke(Method.java:616) 
books.log.6- at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:212) 

Я знаю, что это вызвано Mysql - после нескольких часов ожидания, он initialy закрыт пока он все еще оживает со стороны dbcp. Поскольку Mysql обслуживает несколько экземпляров базы данных, поэтому мне нужно внести изменения со стороны кода приложения.

Мой вопрос в том, действительно ли исключение действительно имеет значение? будет ли повторное соединение JPA после отказа?

Спасибо!

Answer 1

Вы должны добавить запрос проверки (select 1) на ваш DataSource.

<Resource name="jdbc/cfmediaarchive" type="javax.sql.DataSource" 
    driverClassName="com.mysql.jdbc.Driver" 
    url="jdbc:mysql://localhost:3306/mydb?useUnicode=true&amp;characterEncoding=utf8" 

    auth="Container" username="username" password="password" 

    maxIdle="3" maxActive="15" maxWait="10000" logAbandoned="true" removeAbandoned="true" removeAbandonedTimeout="60" 

    validationQuery="select 1" /> 

---

Config с Spring:

spring.xml

<bean id="dataSource" 
    class="org.apache.commons.dbcp.BasicDataSource" 
    destroy-method="close"> 
    <property name="driverClassName" value="${driverClassName}" /> 
    <property name="url" value="${url}" /> 
    <property name="username" value="${username}" /> 
    <property name="password" value="${password}" /> 
    <property name="validationQuery" value="select 1"/> 
</bean> 

    <bean 
    class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean" 
    id="entityManagerFactory"> 
    <property name="persistenceUnitName" value="persistenceUnit" /> 
    <property name="dataSource" ref="dataSource" /> 
    <!-- this is important to connect JPA and JdbcTemplate transaction control --> 
    <property name="jpaVendorAdapter"> 
     <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"> 
      <property name="showSql" value="false" /> 
     </bean> 
    </property> 
</bean> 

persistence.xml

<persistence-unit name="persistenceUnit" transaction-type="RESOURCE_LOCAL"> 
    <provider>org.hibernate.ejb.HibernatePersistence</provider> 
    <properties> 
     <property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5InnoDBDialect" /> 
     <property name="hibernate.hbm2ddl.auto" value="validate" /> 
     <property name="hibernate.connection.charSet" value="UTF-8" /> 
     <property name="hibernate.show_sql" value="false" /> 

    </properties> 
</persistence-unit>