springboot下配置多数据源的方法

下面为您介绍在Spring Boot中配置多数据源的方法。

1. 添加依赖

在 pom.xml 文件中添加以下依赖：

<!-- 数据源驱动依赖 -->
<dependency>
    <groupId>com.zaxxer</groupId>
    <artifactId>HikariCP</artifactId>
</dependency>

<!-- Spring Boot JPA依赖 -> 如果使用Spring Data JPA -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>

2. 配置主数据源

在 application.yml 或 application.properties 文件中，配置主数据源的连接信息：

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/mydb
    username: root
    password: root
    driver-class-name: com.mysql.cj.jdbc.Driver

3. 配置第二个数据源

3.1 创建配置类

创建一个配置类，用来配置第二个数据源的连接信息：

@Configuration
public class DataSourceConfig2 {

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

3.2 在配置文件中配置第二个数据源连接信息

在 application.yml 或 application.properties 文件中添加以下配置信息：

spring:
  datasource:
    secondary:
      url: jdbc:mysql://localhost:3306/mydb2
      username: root
      password: root
      driver-class-name: com.mysql.cj.jdbc.Driver

4. 配置JPA

如果需要使用Spring Data JPA，可以在 pom.xml 中添加以下依赖：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>

<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-core</artifactId>
</dependency>

4.1 创建一个JPA的配置类

@Configuration
@EnableJpaRepositories(
        entityManagerFactoryRef="entityManagerFactory2",
        basePackages= { "com.example.multi.repository.secondary" }) // 指定JPA Repository的位置
public class JpaConfig2 {

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

    @Autowired
    private JpaProperties jpaProperties;

    @Bean(name = "entityManagerFactory2")
    public EntityManagerFactory secondaryEntityManagerFactory(EntityManagerFactoryBuilder builder) {
        LocalContainerEntityManagerFactoryBean factory = builder
                .dataSource(secondaryDataSource)
                // 指定Entity的位置
                .packages("com.example.multi.entity.secondary")
                .persistenceUnit("secondaryPersistenceUnit")
                .properties(jpaProperties.getProperties())
                .build();

        return factory.getObject();
    }

    @Bean(name = "transactionManager2")
    public PlatformTransactionManager secondaryTransactionManager(EntityManagerFactoryBuilder builder) {
        JpaTransactionManager jpaTransactionManager = new JpaTransactionManager();
        jpaTransactionManager.setEntityManagerFactory(secondaryEntityManagerFactory(builder));
        return jpaTransactionManager;
    }
}

4.2 在Service中使用

最后，在Service中使用EntityManager和@Transactional注解来实现对两个库的访问。

@Service
public class UserService {

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

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

    @PersistenceContext(unitName = "secondaryEntityManagerFactory")
    private EntityManager entityManager2;

    @Transactional
    public void save(User user) {
        entityManager.persist(user);
    }

    @Transactional(value = "transactionManager2")
    public void save2(User user) {
        entityManager2.persist(user);
    }
}

示例

示例1: 单个Service内使用两个数据源

@Service
public class UserService {

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

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

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

    @PersistenceContext(unitName = "secondaryEntityManagerFactory")
    private EntityManager entityManager2;

    @Transactional
    public void save(User user) {
        entityManager.persist(user);
    }

    @Transactional(value = "transactionManager2")
    public void save2(User user) {
        entityManager2.persist(user);
    }
}

示例2: 不同Service使用不同的数据源

@Service
public class UserServicePrimary {

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

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

    @Transactional
    public void save(User user) {
        entityManager.persist(user);
    }
}

@Service
public class UserServiceSecondary {

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

    @PersistenceContext(unitName = "secondaryEntityManagerFactory")
    private EntityManager entityManager2;

    @Transactional(value = "transactionManager2")
    public void save2(User user) {
        entityManager2.persist(user);
    }
}

以上就是在Spring Boot中配置多数据源的方法，希望对您有所帮助。

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