Spring Data JPA - Hibernate - 从序列中获取id后关闭事务

Question

我有一个应用程序，它使用Spring Data JPA和Oracle数据库作为后端。 Entity类有一个id列，由数据库中的序列生成。

实体类是：

@Entity
@Table(name="ROLES")
public class AppRole {

    @Id
    @SequenceGenerator(name="SEQ_ROLES", sequenceName="SEQ_ROLES", allocationSize = 1)
    @GeneratedValue(generator="SEQ_ROLES", strategy = GenerationType.SEQUENCE)
    private Long id;

    private String name;

    private String description;

    .. getters and setters
}

和spring数据jpa存储库接口是：

public interface AppRoleRepository extends JpaRepository<AppRole, Long>, JpaSpecificationExecutor<AppRole> {}

但是，每当我试图坚持AppRole的实体时，它都会抛出异常背景，但仍然可以正常工作。页面呈现良好，客户端没有任何反应。但是在服务器控制台中，它会输出这些行;

11:39:35.973 DEBUG JpaTransactionManager - Exposing JPA transaction as JDBC transaction [org.springframework.orm.jpa.vendor.HibernateJpaDialect$HibernateConnectionHandle@640f233e]
11:39:35.977 DEBUG SQL - select SEQ_ROLES.nextval from dual
11:39:36.036 DEBUG SequenceGenerator - Sequence identifier generated: BasicHolder[java.lang.Long[36]]
11:39:36.036 DEBUG AbstractSaveEventListener - Generated identifier: 36, using strategy: org.hibernate.id.SequenceHiLoGenerator
11:39:36.036 DEBUG AbstractFlushingEventListener - Processing flush-time cascades
11:39:36.036 DEBUG AbstractFlushingEventListener - Dirty checking collections
11:39:36.037 DEBUG AbstractFlushingEventListener - Flushed: 1 insertions, 0 updates, 0 deletions to 1 objects
11:39:36.037 DEBUG AbstractFlushingEventListener - Flushed: 0 (re)creations, 0 updates, 0 removals to 0 collections
11:39:36.037 DEBUG EntityPrinter - Listing entities:
11:39:36.037 DEBUG EntityPrinter - AppRole{name=asdasd, description=asdasd, id=36}
11:39:36.051 DEBUG SQL - insert into ROLES (description, name, id) values (?, ?, ?)
11:39:36.091 DEBUG SqlExceptionHelper - could not log warnings
java.sql.SQLRecoverableException: Closed Statement
    at oracle.jdbc.driver.OracleClosedStatement.getWarnings(OracleClosedStatement.java:6501) ~[ojdbc6-11.2.0.4.jar:11.2.0.3.0]
    at oracle.jdbc.driver.OracleStatementWrapper.getWarnings(OracleStatementWrapper.java:1571) ~[ojdbc6-11.2.0.4.jar:11.2.0.3.0]
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.handleAndClearWarnings(SqlExceptionHelper.java:291) ~[hibernate-core-4.2.18.Final.jar:4.2.18.Final]

我有这个例外。看来，从序列中获取id后，事务和连接都会关闭。然后它恢复并打开一个新连接并在这个新连接中执行此insert语句。

这是正常的，或者我误用或错误配置了什么错误？

非常感谢。

编辑：配置文件，服务实施和POM

持久性配置是：

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories("com.company.core.repository")
public class PersistenceConfig {

    private @Autowired Constants constants;

    @Autowired
    private DataSource dataSource;

    @Autowired
    private EntityManagerFactory entityManagerFactory;


    @Bean(name = "dataSource")
    public DataSource getDataSource() {
        DriverManagerDataSource ds = new DriverManagerDataSource(
                constants.getJdbcUrl(), constants.getJdbcName(),
                constants.getJdbcPass());
        ds.setDriverClassName(tfConstants.getJdbcDriver());
        return ds;
    }

    @Bean
    public AbstractEntityManagerFactoryBean entityManagerFactory() {
        LocalContainerEntityManagerFactoryBean emFactory = new LocalContainerEntityManagerFactoryBean();

        emFactory.setDataSource(dataSource);
        emFactory.setPackagesToScan(constants.getApplicationPackageToScan());
        emFactory.setPersistenceProviderClass(HibernatePersistence.class);
        emFactory.setJpaProperties(getHibernateProperties());
        emFactory.setJpaVendorAdapter(new HibernateJpaVendorAdapter());

        return emFactory;
    }

    private Properties getHibernateProperties() {
        Properties hp = new Properties();

        hp.setProperty("hibernate.dialect", "org.hibernate.dialect.Oracle10gDialect");
        hp.setProperty("show_sql", "true");
        hp.setProperty("hibernate.connection.release_mode", "after_transaction");
        hp.setProperty("hibernate.current_session_factory_class", "thread");

        return hp;
    }

    @Bean(name="transactionManager")
    public AbstractPlatformTransactionManager getTransactionManager() {
        JpaTransactionManager jpaTran = new JpaTransactionManager();
        jpaTran.setEntityManagerFactory(entityManagerFactory);
        return jpaTran;
    }

}

服务实施是：

@Service
public class AppRoleService {

    private @Resource AppRoleRepository roleRepo;

    public void save(AppRole role) {
        roleRepo.save(role);
    }

}

和pom.xml：

...
<properties>
    <java.version>1.7</java.version>

    <spring.version>4.1.5.RELEASE</spring.version>

    <hibernate.version>4.2.18.Final</hibernate.version>
    <spring.data.jpa>1.7.2.RELEASE</spring.data.jpa>
</properties>

<dependencies>

    <!-- Spring dependencies -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <dependency>
        <groupId>org.springframework.data</groupId>
        <artifactId>spring-data-jpa</artifactId>
        <version>${spring.data.jpa}</version>
        <exclusions>
            <exclusion>
                <artifactId>spring-asm</artifactId>
                <groupId>org.springframework</groupId>
            </exclusion>
        </exclusions>
    </dependency>

    <!-- Hibernate -->
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-core</artifactId>
        <version>${hibernate.version}</version>
    </dependency>

    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-validator</artifactId>
        <version>${hibernate.validation.version}</version>
    </dependency>

    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>${hibernate.version}</version>
    </dependency>

</dependencies>
...