Spring Boot 多数据源配置（JPA）

编程经验分享2024-09-07 21:55

目录

前言

前置环境

pom

yml

Entity

Dao

Config

Controller

演示

前言

一般一个系统至少有一个数据源，用来持久化业务数据以及查询。单个数据源的系统很常见，在 Spring Boot 框架下配置也很简单。在约定大于配置这个思想下，只需要在配置文件中简单配置下数据库连接信息就行了。

除了单数据源系统，在实际工作中，还会遇到多数据源系统。有可能是因为业务需要，以实际中做过的资产清查相关的项目为例，数据的存储分成了两个库，一个当前库和归档库，系统就需要配置两个数据源来满足业务需求。也有可能是技术架构，比如 MySQL 数据库使用了主从复制架构来实现读写分离，然后在应用层做分流，就需要配置主库和从库数据源，并在代码中决定使用哪个库进行数据库操作。

以下是Spring Boot JPA 多数据源的配置教程

前置环境

JDK8 + SringBoot2 + MySQL8

分别创建数据库 test1 test2

分别在两个数据库中创建 user 表

create table user (

id int auto_increment primary key,

username varchar(255),

password varchar(255)

);

在test1.user 表中插入数据

insert into user(username, password) values('张三', '123456');

在test2.user 表中插入数据

insert into user(username, password) values('李四', '123456');

pom

XML 复制代码 
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>${spring-boot.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
 
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
 
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
 
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
    <dependencies>

yml

复制代码 
server:
  port: 8888

spring:
  datasource:
    primary:
      url: jdbc:mysql://localhost:3306/test1?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=UTC&allowPublicKeyRetrieval=true
      username: root
      password: mysql
      driver-class-name: com.mysql.cj.jdbc.Driver
    secondary:
      url: jdbc:mysql://localhost:3306/test2?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=UTC&allowPublicKeyRetrieval=true
      username: root
      password: mysql
      driver-class-name: com.mysql.cj.jdbc.Driver

  jpa:
    primary:
      show-sql: true
      properties:
        hibernate:
          hbm2ddl:
            auto: update
          dialect: org.hibernate.dialect.MySQL5InnoDBDialect
    secondary:
      show-sql: true
      properties:
        hibernate:
          hbm2ddl:
            auto: update
          dialect: org.hibernate.dialect.MySQL5InnoDBDialect

Entity

主库和从库的实体类需要放在不同的包下，以本文为例

主库的实体类包路径为：com.jpa.entity.primary

java 复制代码 
@Entity
@Table ( name = "user")
public class PrimaryUserEntity {
    private Integer id;
    private String username;
    private String password;

    @Id
    @GeneratedValue ( strategy = GenerationType.IDENTITY)
    @Column ( name = "id" )
    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

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

    public void setUsername(String username) {
        this.username = username;
    }

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

    public void setPassword(String password) {
        this.password = password;
    }

}

从库的实体类包路径为：com.jpa.entity.secondary

java 复制代码 
@Entity
@Table ( name = "user")
public class SecondaryUserEntity {
    private Integer id;
    private String username;
    private String password;

    @Id
    @GeneratedValue ( strategy = GenerationType.IDENTITY)
    @Column ( name = "id" )
    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

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

    public void setUsername(String username) {
        this.username = username;
    }

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

    public void setPassword(String password) {
        this.password = password;
    }

}

Dao

主库和从库的Dao需要放在不同的包下，以本文为例

主库的Dao包路径为：com.jpa.dao.primary

java 复制代码 
@Repository (value = IPrimaryUserDao.DAO_BEAN_NAME )
public interface IPrimaryUserDao extends JpaRepository<PrimaryUserEntity, Integer> {
    String DAO_BEAN_NAME = "primaryUserDao";
}

从库的Dao包路径为：com.jpa.dao.secondary

java 复制代码 
@Repository (value = ISecondaryUserDao.DAO_BEAN_NAME )
public interface ISecondaryUserDao extends JpaRepository<SecondaryUserEntity, Integer> {
    String DAO_BEAN_NAME = "secondaryUserDao";
}

Config

记得将类中的两个包路径修改成自己项目的包路径

REPOSITORY_PACKAGE

ENTITY_PACKAGE

主库数据源配置

java 复制代码 
@Configuration
@EnableTransactionManagement
@EnableJpaRepositories (
        basePackages = PrimaryDatasourceAndJpaConfig.REPOSITORY_PACKAGE,
        entityManagerFactoryRef = "primaryEntityManagerFactory",
        transactionManagerRef = "primaryTransactionManager"
)
public class PrimaryDatasourceAndJpaConfig {

    private static final String REPOSITORY_PACKAGE = "com.jpa.dao.primary";
    private static final String ENTITY_PACKAGE = "com.jpa.entity.primary";

    //--------------数据源配置-------------------

    /**
     * 扫描spring.datasource.primary开头的配置信息
     *
     * @return 数据源配置信息
     */
    @Primary
    @Bean(name = "primaryDataSourceProperties")
    @ConfigurationProperties(prefix = "spring.datasource.primary")
    public DataSourceProperties dataSourceProperties() {
        return new DataSourceProperties();
    }

    /**
     * 取主库数据源对象
     *
     * @param dataSourceProperties 注入名为primaryDataSourceProperties的bean
     * @return 数据源对象
     */
    @Primary
    @Bean(name = "primaryDataSource")
    public DataSource dataSource(@Qualifier("primaryDataSourceProperties") DataSourceProperties dataSourceProperties) {
        return dataSourceProperties.initializeDataSourceBuilder().build();
    }


    /**
     * 扫描spring.jpa.primary开头的配置信息
     *
     * @return jpa配置信息
     */
    @Primary
    @Bean (name = "primaryJpaProperties")
    @ConfigurationProperties (prefix = "spring.jpa.primary")
    public JpaProperties jpaProperties() {
        return new JpaProperties();
    }

    /**
     * 获取主库实体管理工厂对象
     *
     * @param primaryDataSource 注入名为primaryDataSource的数据源
     * @param jpaProperties     注入名为primaryJpaProperties的jpa配置信息
     * @param builder           注入EntityManagerFactoryBuilder
     * @return 实体管理工厂对象
     */
    @Primary
    @Bean(name = "primaryEntityManagerFactory")
    public LocalContainerEntityManagerFactoryBean entityManagerFactoryBean(
            @Qualifier ("primaryDataSource") DataSource primaryDataSource,
            @Qualifier("primaryJpaProperties") JpaProperties jpaProperties,
            EntityManagerFactoryBuilder builder
    ) {
        return builder
                // 设置数据源
                .dataSource(primaryDataSource)
                // 设置jpa配置
                .properties(jpaProperties.getProperties())
                // 设置实体包名
                .packages(ENTITY_PACKAGE)
                // 设置持久化单元名，用于@PersistenceContext注解获取EntityManager时指定数据源
                .persistenceUnit("primaryPersistenceUnit").build();
    }

    /**
     * 获取实体管理对象
     *
     * @param factory 注入名为primaryEntityManagerFactory的bean
     * @return 实体管理对象
     */
    @Primary
    @Bean(name = "primaryEntityManager")
    public EntityManager entityManager(@Qualifier("primaryEntityManagerFactory") EntityManagerFactory factory) {
        return factory.createEntityManager();
    }

    /**
     * 获取主库事务管理对象
     *
     * @param factory 注入名为primaryEntityManagerFactory的bean
     * @return 事务管理对象
     */
    @Primary
    @Bean(name = "primaryTransactionManager")
    public JpaTransactionManager transactionManager(@Qualifier("primaryEntityManagerFactory") EntityManagerFactory factory) {
        return new JpaTransactionManager(factory);
    }
}

从库数据源配置

java 复制代码 
@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        basePackages = SecondaryDatasourceAndJpaConfig.REPOSITORY_PACKAGE,
        entityManagerFactoryRef = "secondaryEntityManagerFactory",
        transactionManagerRef = "secondaryTransactionManager"
)
public class SecondaryDatasourceAndJpaConfig {
    
    static final String REPOSITORY_PACKAGE = "com.jpa.dao.secondary";
    static final String ENTITY_PACKAGE = "com.jpa.entity.secondary";

    //--------------数据源配置-------------------

    /**
     * 扫描spring.datasource.secondary开头的配置信息
     *
     * @return 数据源配置信息
     */
    @Bean(name = "secondaryDataSourceProperties")
    @ConfigurationProperties(prefix = "spring.datasource.secondary")
    public DataSourceProperties dataSourceProperties() {
        return new DataSourceProperties();
    }

    /**
     * 获取次数据源对象
     *
     * @param dataSourceProperties 注入名为secondaryDataSourceProperties的bean
     * @return 数据源对象
     */
    @Bean("secondaryDataSource")
    public DataSource dataSource(@Qualifier("secondaryDataSourceProperties") DataSourceProperties dataSourceProperties) {
        return dataSourceProperties.initializeDataSourceBuilder().build();
    }

    /**
     * 扫描spring.jpa.secondary
     *
     * @return jpa配置信息
     */
    @Bean(name = "secondaryJpaProperties")
    @ConfigurationProperties(prefix = "spring.jpa.secondary")
    public JpaProperties jpaProperties() {
        return new JpaProperties();
    }

    /**
     * 获取次库实体管理工厂对象
     *
     * @param secondaryDataSource 注入名为secondaryDataSource的数据源
     * @param jpaProperties       注入名为secondaryJpaProperties的jpa配置信息
     * @param builder             注入EntityManagerFactoryBuilder
     * @return 实体管理工厂对象
     */
    @Bean(name = "secondaryEntityManagerFactory")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory(
            @Qualifier("secondaryDataSource") DataSource secondaryDataSource,
            @Qualifier("secondaryJpaProperties") JpaProperties jpaProperties,
            EntityManagerFactoryBuilder builder
    ) {
        return builder
                // 设置数据源
                .dataSource(secondaryDataSource)
                // 设置jpa配置
                .properties(jpaProperties.getProperties())
                // 设置实体包名
                .packages(ENTITY_PACKAGE)
                // 设置持久化单元名，用于@PersistenceContext注解获取EntityManager时指定数据源
                .persistenceUnit("secondaryPersistenceUnit").build();
    }

    /**
     * 获取实体管理对象
     *
     * @param factory 注入名为secondaryEntityManagerFactory的bean
     * @return 实体管理对象
     */
    @Bean(name = "secondaryEntityManager")
    public EntityManager entityManager(@Qualifier("secondaryEntityManagerFactory") EntityManagerFactory factory) {
        return factory.createEntityManager();
    }

    /**
     * 获取事务管理对象
     *
     * @param factory 注入名为secondaryEntityManagerFactory的bean
     * @return 事务管理对象
     */
    @Bean(name = "secondaryTransactionManager")
    public JpaTransactionManager transactionManager(@Qualifier("secondaryEntityManagerFactory") EntityManagerFactory factory) {
        return new JpaTransactionManager(factory);
    }
}

Controller

主库

java 复制代码 
@RestController
@RequestMapping(value = "/primary")
public class PrimaryJpaController {

    @Resource
    private IPrimaryUserDao primaryUserDao;

    @RequestMapping(value = "/findAll", method = RequestMethod.GET)
    public List<PrimaryUserEntity> findAll() {
        return primaryUserDao.findAll();
    }
}

从库

java 复制代码 
@RestController
@RequestMapping(value = "/secondary")
public class SecondaryJpaController{

    @Resource
    private ISecondaryUserDao secondaryUserDao;

    @RequestMapping(value = "/findAll", method = RequestMethod.GET)
    public List<SecondaryUserEntity> findAll() {
        return secondaryUserDao.findAll();
    }
}

演示

请求 /primary/findAll

请求 /secondary/findAll

相关推荐
utmhikari26 分钟前
【架构艺术】Go语言微服务monorepo的代码架构设计
后端·微服务·架构·golang·monorepo
蜡笔小新星29 分钟前
Flask项目框架
开发语言·前端·经验分享·后端·python·学习·flask
计算机学姐33 分钟前
基于Asp.net的驾校管理系统
vue.js·后端·mysql·sqlserver·c#·asp.net·.netcore
欢乐少年19042 小时前
SpringBoot集成Sentry日志收集-3 (Spring Boot集成)
spring boot·后端·sentry
夏天的味道٥3 小时前
使用 Java 执行 SQL 语句和存储过程
java·开发语言·sql
冰糖码奇朵5 小时前
大数据表高效导入导出解决方案，mysql数据库LOAD DATA命令和INTO OUTFILE命令详解
java·数据库·sql·mysql
好教员好5 小时前
【Spring】整合【SpringMVC】
java·spring
浪九天6 小时前
Java直通车系列13【Spring MVC】（Spring MVC常用注解）
java·后端·spring
堕落年代7 小时前
Maven匹配机制和仓库库设置
java·maven
功德+n7 小时前
Maven 使用指南：基础 + 进阶 + 高级用法
java·开发语言·maven
热门推荐
01DeepSeek各版本说明与优缺点分析02从零安装 LLaMA-Factory 微调 Qwen 大模型成功及所有的坑03如何在WPS和Word/Excel中直接使用DeepSeek功能04苍穹外卖面试总结05DeepSeek R1本地化部署 Ollama + Chatbox 打造最强 AI 工具06本地部署DeepSeek教程（Mac版本）07Coze扣子平台完整体验和实践（附国内和国际版对比）08Windows 11 安装 Dify 完整指南 非docker环境09保姆级教程：利用Ollama与Open-WebUI本地部署 DeedSeek-R1大模型10macOS 上部署 RAGFlow