Springboot使用JPA配置多数据源

本人在最近的项目中，需要使用JPA配置两个数据源来完成一些功能，以此记录配置过程。方便以后使用：

 第一步：配置文件中加入相应的配置。

spring.jpa.hibernate.ddl-auto=none
spring.jpa.show-sql=true
spring.jpa.database=mysql

#预发环境数据库
spring.datasource.primary.jdbc-url=jdbc:mysql://localhost:3306/toutiao?characterEncoding=utf8&useSSL=false&serverTimezone=Asia/Shanghai
spring.datasource.primary.username=root
spring.datasource.primary.password=123456
spring.datasource.primary.driver-class-name=com.mysql.cj.jdbc.Driver

#预发环境数据库
spring.datasource.secondary.jdbc-url=jdbc:mysql://localhost:3306/driver_manager?characterEncoding=utf8&useSSL=false&serverTimezone=Asia/Shanghai
spring.datasource.secondary.username=root
spring.datasource.secondary.password=123456
spring.datasource.secondary.driver-class-name=com.mysql.cj.jdbc.Driver

第二步：加入对应的配置类。

1、DataSourceConfig类，配置两个数据源。

@Configuration
public class DataSourceConfig {
  @Bean(name = "primaryDataSource")
  @Qualifier("primaryDataSource")
  @Primary
  @ConfigurationProperties(prefix = "spring.datasource.primary")
  public DataSource primaryDbDataSource() {
    return DataSourceBuilder.create().build();
  }

  @Bean(name = "secondaryDataSource")
  @Qualifier("secondaryDataSource")
  @ConfigurationProperties(prefix = "spring.datasource.secondary")
  public DataSource secondaryDbDataSource() {
    return DataSourceBuilder.create().build();
  }

}

2、主数据源配置类，PrimaryConfig类。

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
    entityManagerFactoryRef = "entityManagerFactoryPrimary",
    transactionManagerRef = "transactionManagerPrimary",
    basePackages = {"com.kunkun.jpa.primary"}    //需要修改的地方
)
public class PrimaryConfig {
  private String url;

  public String getUrl() {
    return url;
  }

  public void setUrl(String url) {
    this.url = url;
  }

  @Autowired
  @Qualifier("primaryDataSource")
  private DataSource primaryDataSource;

  @Primary
  @Bean(name = "entityManagerPrimary")
  public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
    return entityManagerFactoryPrimary(builder).getObject().createEntityManager();
  }

  @Primary
  @Bean(name = "entityManagerFactoryPrimary")
  public LocalContainerEntityManagerFactoryBean entityManagerFactoryPrimary(
      EntityManagerFactoryBuilder builder) {
    return builder
        .dataSource(primaryDataSource)
        .properties(getVendorProperties())
        .packages("com.kunkun.jpa.model.primary")         //设置实体类所在位置与副数据源区分，需要修改
        .persistenceUnit("primaryPersistenceUnit")
        .build();
  }

  private Map getVendorProperties() {
    HashMap properties = new HashMap<>();
    properties.put("hibernate.dialect",
        env.getProperty("hibernate.dialect"));
    properties.put("hibernate.ddl-auto",
        "create");
    properties.put("hibernate.physical_naming_strategy",
        "org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy");
    properties.put("hibernate.implicit_naming_strategy",
        "org.springframework.boot.orm.jpa.hibernate.SpringImplicitNamingStrategy");
    return properties;
  }

  @Autowired
  private Environment env;

  @Primary
  @Bean(name = "transactionManagerPrimary")
  public PlatformTransactionManager transactionManagerPrimary(EntityManagerFactoryBuilder builder) {
    return new JpaTransactionManager(entityManagerFactoryPrimary(builder).getObject());
  }

}

3、SecondaryConfig，辅数据源配置

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
    entityManagerFactoryRef = "entityManagerFactorySecondary",
    transactionManagerRef = "transactionManagerSecondary",
    basePackages = {"com.kunkun.jpa.secondary"}) //设置DAO接口层所在包位置与主数据源区分
public class SecondaryConfig {

  @Autowired
  @Qualifier("secondaryDataSource")
  private DataSource secondaryDataSource;

  @Bean(name = "entityManagerSecondary")
  public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
    return entityManagerFactorySecondary(builder).getObject().createEntityManager();
  }

  @Bean(name = "entityManagerFactorySecondary")
  public LocalContainerEntityManagerFactoryBean entityManagerFactorySecondary(EntityManagerFactoryBuilder builder) {
    return builder
        .dataSource(secondaryDataSource)
        .properties(getVendorProperties())
        .packages("com.kunkun.jpa.model.secondary")      //设置实体类所在包的位置与主数据源区分
        .persistenceUnit("primaryPersistenceUnit")
        .build();
  }

  private Map getVendorProperties() {
    HashMap properties = new HashMap<>();
    properties.put("hibernate.hbm2ddl.auto",
        env.getProperty("hibernate.hbm2ddl.auto"));
    properties.put("hibernate.ddl-auto",
        env.getProperty("update"));
    properties.put("hibernate.dialect",
        env.getProperty("hibernate.dialect"));
    properties.put("hibernate.physical_naming_strategy",
        "org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy");
    properties.put("hibernate.implicit_naming_strategy",
        "org.springframework.boot.orm.jpa.hibernate.SpringImplicitNamingStrategy");
    return properties;
  }

  @Autowired
  private Environment env;

  @Bean(name = "transactionManagerSecondary")
  PlatformTransactionManager transactionManagerSecondary(EntityManagerFactoryBuilder builder) {
    return new JpaTransactionManager(entityManagerFactorySecondary(builder).getObject());
  }
}

第三步：设置实体类所在位置

实体类：

@Entity
@Data
@Table(name = "user")
public class User {
    @Id
    private Integer id;
    /**
     * 名字
     */
    private String name;

    /**
     * 密码
     */
    private String password;
}

DAO类：

public interface UserDao extends JpaRepository,
    JpaSpecificationExecutor {

    /**
     * 根据title查数据
     *
     * @param id
     * @return
     */
    @Transactional
    @Query("SELECT dr.name from User dr where dr.id = :id")
    String findDataByTitle(@Param("id") Integer id);
}

上面标红的地方是需要修改的地方，对于配置文件和数据源配置类的部分是可以修改的。建议名字不修改，直接复制就好了。