Spring Boot集成mybatis 多数据源

Myth丶恋晨 2022-05-15 14:17 250阅读 0赞

### 多数据源之静态方法 ###

目标：我们要从同一个方法中取出不同数据库的数据

效果：

GetMapping("/1")
    	public void test() {
    		System.out.println("shiro数据库："+um2.get(1));
    		System.out.println("springboot数据库："+um1.get(1));
    	}

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思路：我们要写两个数据库的配置，然后创建datasource，transaction，sqlSessionFactory

#datasource1
    master1.datasource.url=jdbc:mysql://localhost:3306/springboot
    master1.datasource.username=root
    master1.datasource.password=
    master1.datasource.driverClassName=com.mysql.jdbc.Driver
    
    
    #datasource2
    master2.datasource.url=jdbc:mysql://localhost:3306/shiro
    master2.datasource.username=root
    master2.datasource.password=
    master2.datasource.driverClassName=com.mysql.jdbc.Driver

我们要读取配置文件的数据库配置，注入mapper

@Configuration
    // 扫描 Mapper 接口并容器管理
    @MapperScan(basePackages = Master2DataSourceConfig.PACKAGE, sqlSessionFactoryRef = "master2SqlSessionFactory")
    public class Master2DataSourceConfig {
            // 精确到 master 目录，以便跟其他数据源隔离
            static final String PACKAGE = "com.Tom.mapper2";
            static final String MAPPER_LOCATION = "com/tom/mapper2/userMapper.xml";
     
            @Value("${master2.datasource.url}")
            private String url;
     
            @Value("${master2.datasource.username}")
            private String user;
     
            @Value("${master2.datasource.password}")
            private String password;
     
            @Value("${master2.datasource.driverClassName}")
            private String driverClass;
     
            @Bean(name = "master2DataSource")
            public DataSource master2DataSource() {
                DruidDataSource dataSource = new DruidDataSource();
                dataSource.setDriverClassName(driverClass);
                dataSource.setUrl(url);
                dataSource.setUsername(user);
                dataSource.setPassword(password);
                System.out.println("数据库2创建OK！！");
                return dataSource;
            }
     
            @Bean(name = "master2TransactionManager")
            public DataSourceTransactionManager master2TransactionManager() {
            	System.out.println("事务管理器2创建OK！！");
                return new DataSourceTransactionManager(master2DataSource());
            }
     
            @Bean(name = "master2SqlSessionFactory")
            public SqlSessionFactory clusterSqlSessionFactory(@Qualifier("master2DataSource") DataSource master2DataSource) throws Exception {
                final SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
                sessionFactory.setDataSource(master2DataSource);
                sessionFactory.setMapperLocations(new PathMatchingResourcePatternResolver()
                        .getResources(Master2DataSourceConfig.MAPPER_LOCATION));
                System.out.println("sql工厂2创建ok！！");
                return sessionFactory.getObject();
        }
    }

@Configuration
    // 扫描 Mapper 接口并容器管理
    @MapperScan(basePackages = Master1DataSourceConfig.PACKAGE, sqlSessionFactoryRef = "master1SqlSessionFactory")
    public class Master1DataSourceConfig {
        // 精确到 master 目录，以便跟其他数据源隔离
        static final String PACKAGE = "com.tom.mapper1";
        static final String MAPPER_LOCATION = "com/tom/mapper1/userMapper.xml";
     
        @Value("${master1.datasource.url}")
        private String url;
     
        @Value("${master1.datasource.username}")
        private String user;
     
        @Value("${master1.datasource.password}")
        private String password;
     
        @Value("${master1.datasource.driverClassName}")
        private String driverClass;
     
        @Bean(name = "master1DataSource")
        @Primary
        public DataSource masterDataSource() {
            DruidDataSource dataSource = new DruidDataSource();
            dataSource.setDriverClassName(driverClass);
            dataSource.setUrl(url);
            dataSource.setUsername(user);
            dataSource.setPassword(password);
            System.out.println("数据库1创建OK！！");
            return dataSource;
        }
     
        @Bean(name = "master1TransactionManager")
        @Primary
        public DataSourceTransactionManager masterTransactionManager() {
        	System.out.println("事务管理器1创建OK！！");
            return new DataSourceTransactionManager(masterDataSource());
        }
     
        @Bean(name = "master1SqlSessionFactory")
        @Primary
        public SqlSessionFactory masterSqlSessionFactory(@Qualifier("master1DataSource") DataSource masterDataSource)
                throws Exception {
            final SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
            sessionFactory.setDataSource(masterDataSource);
            sessionFactory.setMapperLocations(new PathMatchingResourcePatternResolver()
                    .getResources(Master1DataSourceConfig.MAPPER_LOCATION));
            System.out.println("sql工厂1创建ok！！");
            return sessionFactory.getObject();
        }
    }

@Primary 标志这个 Bean 如果在多个同类 Bean 候选时，该 Bean 优先被考虑。「多数据源配置的时候注意，必须要有一个主数据源，用 @Primary 标志该 Bean」  
@MapperScan 扫描 Mapper 接口并容器管理，包路径精确到 master，为了和下面 cluster 数据源做到精确区分  
@Value 获取全局配置文件 application.properties 的 kv 配置,并自动装配  
sqlSessionFactoryRef 表示定义了 key ，表示一个唯一 SqlSessionFactory 实例

mapper需要分开写

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMDA4NTM1_size_16_color_FFFFFF_t_70 1][]

@RestController
    public class testController {
    	@Autowired
    	private userMapper1 um1;
    	@Autowired
    	private userMapper2 um2;
    	@GetMapping("/1")
    	public void test() {
    		System.out.println("shiro数据库："+um2.get(1));
    		System.out.println("springboot数据库："+um1.get(1));
    	}
    }

好处：简单可用，易配置

坏处：局限较大，不易扩展

### 多数据源之动态方式 ###

[https://blog.csdn.net/maoyeqiu/article/details/74011626][https_blog.csdn.net_maoyeqiu_article_details_74011626]

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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQwMDA4NTM1_size_16_color_FFFFFF_t_70 1]: /images/20220503/9bb1238a85ea4560bbf9df0cbeeb3318.png
[https_blog.csdn.net_maoyeqiu_article_details_74011626]: https://blog.csdn.net/maoyeqiu/article/details/74011626