java - EntityManager 持久化和合并在 @Transactional 方法中不起作用

Question

我的 @Transactional 注释和 EntityManager 持久和合并方法有奇怪的行为。我已将方法注释为 @Transactional，并在其中调用 EntityManager.persists(entity)...但没有任何反应。实体没有保存到数据库，没有引发异常，完全没有。我读过大量的例子，SO问题，我的代码看起来不错，但不起作用。

hibernate 配置:

import org.hibernate.jpa.HibernatePersistenceProvider;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.DependsOn;
import org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor;
import org.springframework.jndi.JndiTemplate;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;

import javax.naming.NamingException;
import javax.sql.DataSource;
import java.sql.Connection;
import java.util.Properties;

@Configuration
@EnableTransactionManagement
@ComponentScan(basePackages = {"com.mycompany"})
@DependsOn({"PropertiesConfig"})
public class HibernateConfig {

    public HibernateConfig() {}

    @Bean
    public DataSource dataSource() throws NamingException {
        return (DataSource) new JndiTemplate().lookup(PropertyService.getInstance().getProperty("jndi.jdbc.AGSQL"));
    }

    @Bean(name = "entityManager")
    @DependsOn("dataSource")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory() throws NamingException {
        System.out.println("*** Init EntityManagerFactory ***");
        LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
        em.setPersistenceProviderClass(HibernatePersistenceProvider.class);
        em.setDataSource(dataSource());
        em.setPackagesToScan(new String[] { "com.mycompany" });
        em.setJpaVendorAdapter(new HibernateJpaVendorAdapter());
        em.setJpaProperties(hibernateProperties());
        return em;
    }

    @Bean(name = "tm")
    public PlatformTransactionManager transactionManager() throws NamingException {
        System.out.println("*** Init TransactionManager ***");
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(entityManagerFactory().getObject());
        return transactionManager;
    }

    @Bean
    public PersistenceExceptionTranslationPostProcessor exceptionTranslation() {
        return new PersistenceExceptionTranslationPostProcessor();
    }

    private Properties hibernateProperties() {
        return new Properties() {
            {
                setProperty("hibernate.dialect", PropertyService.getInstance().getProperty("hibernate.dialect"));
                setProperty("show_sql", PropertyService.getInstance().getProperty("show_sql"));
                setProperty("hibernate.connection.isolation", String.valueOf(Connection.TRANSACTION_READ_UNCOMMITTED));
            }
        };
    }
}

实体:

import org.hibernate.annotations.UpdateTimestamp;    
import javax.persistence.*;
import java.time.LocalDateTime;

@Entity
@Table(name = "Vehicle", schema = "dbo")
public class VehicleEntity {
    private Long deviceId;
    private LocalDateTime dtEdit;
    private String name;

    @Id
    @Column(name = "device_id")
    public Long getDeviceId() {
        return deviceId;
    }

    public void setDeviceId(Long deviceId) {
        this.deviceId = deviceId;
    }

    @Basic
    @Column(name = "dt_edit")
    @UpdateTimestamp
    public LocalDateTime getDtEdit() {
        return dtEdit;
    }

    public void setDtEdit(LocalDateTime dtEdit) {
        this.dtEdit = dtEdit;
    }

    @Basic
    @Column(name = "name")
    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

}

道:

import com.mycompany.VehicleEntity;
import org.springframework.transaction.annotation.Transactional;

import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;

@Repository
public class VehicleDao {

    @PersistenceContext(unitName = "entityManager")
    private EntityManager entityManager;

    protected EntityManager getEntityManager() {
        return entityManager;
    }

    @Transactional(transactionManager = "tm")
    public void persist(VehicleEntity entity) {
        getEntityManager().persist(entity);
    }

    @Transactional("tm")
    public void merge(VehicleEntity entity) {
        getEntityManager().merge(entity);
    }

}

执行这段代码完全没有任何作用:

VehicleEntity ve = new VehicleEntity();
ve.setDeviceId(111L);
ve.setName("111");
vehicleDao.persist(ve);

我尝试在persist方法中检查交易状态:

((Session)this.getEntityManager().getDelegate()).getTransaction().getStatus() = NOT_ACTIVE

所以我可以得出结论，事务还没有开始，或者已经开始，但是entitymanager没有自动看到它(见下文)。在其中一个问题中，我看到在调用 persist(entity) 之前，实体管理器已加入事务并做了同样的事情:

@Transactional(transactionManager = "tm")
public void persist(T entity) {
    getEntityManager().joinTransaction();
    getEntityManager().persist(entity);
}

啊啊……它有效。并且交易状态变为ACTIVE。

所以我的问题是: - 为什么没有joinTransaction()它就不起作用？我从来没有在例子中见过它...... -(可能在解决第一个问题之后，这个问题就没有意义了)持久化和合并实际上是在抽象 dao 类中，但是我有很多实体，很多实体 dao 和其中的很多自定义方法。在每个事务中调用 joinTransaction() 并不是一个好主意。如何让它变得漂亮？

编辑:

又检查了一件事 - 添加了传播属性:

@Transactional(transactionManager = "tm", propagation = Propagation.MANDATORY)
public void persist(T entity) {
    getEntityManager().persist(entity);
}

它抛出一个异常:

org.springframework.transaction.IllegalTransactionStateException: No existing transaction found for transaction marked with propagation 'mandatory'

编辑2:

Spring version 5.1.7.RELEASE 
Hibernate version 5.4.10.Final
javax.persistence:javax.persistence-api:2.2 (dependency from hibernate-core)

Answer 1

终于发现问题了:我从 SessionFactory 迁移到 EntityManager 并在配置文件中保留 SessionFactory 的旧设置。问题是事务管理器对于 SF 和 EM 有相同的方法名称:

@Bean(name = "transactionManager")
public PlatformTransactionManager transactionManager(SessionFactory sessionFactory) {
    JpaTransactionManager transactionManager = new JpaTransactionManager();
    transactionManager.setEntityManagerFactory(sessionFactory);
    return transactionManager;
}

@Bean(name = "tm")
public PlatformTransactionManager transactionManager(@Qualifier("customEntityManager") EntityManagerFactory emf) {
    System.out.println("*** Init TransactionManager ***");
    JpaTransactionManager transactionManager = new JpaTransactionManager();
    transactionManager.setEntityManagerFactory(emf);
    return transactionManager;
}

尽管 bean 名称不同，但这是错误的。 将 SF 事务管理器方法更改为 sessionTransactionManager(...) 可以解决该问题。