SpringBoot 动态数据源用注解切换

末蓝、 2022-05-15 15:23 488阅读 0赞

使用版本SpringBoot 1.5.9

动态切换数据源,mysql ,oracle 在项目中动态切换,或者 两个mysql进行切换

> 引入依赖

<dependency>
    	<groupId>com.alibaba</groupId>
    	<artifactId>druid-spring-boot-starter</artifactId>
    	<version>1.1.6</version>
    </dependency>
    <dependency>
    	<groupId>org.mybatis.spring.boot</groupId>
    	<artifactId>mybatis-spring-boot-starter</artifactId>
    </dependency>
    
    <dependency>
    	<groupId>org.springframework.boot</groupId>
    	<artifactId>spring-boot-starter-aop</artifactId>
    </dependency>

> 配置代码

/**
     * Created by XuLingLin on 2019/2/18
     */
    public class DynamicDataSource extends AbstractRoutingDataSource {
    
        //切换数据源
        @Override
        protected Object determineCurrentLookupKey() {
            return DatabaseContextHolder.getDatabaseType();
        }
    }
    
    
    @Component
    public class DatabaseContextHolder {
        //创建 ThreadLocal 用余存储唯一的线程变量
        private static final ThreadLocal<DatabaseType> contextHolder = new ThreadLocal<>();
    
        //添加
        public static void setDatabaseType(DatabaseType type) {
            contextHolder.set(type);
        }
        //获取
        public static DatabaseType getDatabaseType() {
            return contextHolder.get();
        }
        //删除   
        /*
         *注意使用完成之后 需要删除线程变量 
         *ThreadLocal不会自动清理
         */
        public static void clearDBKey() { contextHolder.remove(); }
    
    }
    
    //定义一个枚举对应名称
    public enum DatabaseType {
        mysql1,mysql2
    }
    
    //自定义注解
    @Target({ ElementType.METHOD})
    @Retention(RetentionPolicy.RUNTIME)
    public @interface TargetDataSource {
        DatabaseType value();
    }
    
    //配置类
    
    @Configuration
    @MapperScan("xxxx")//包名
    @EnableTransactionManagement
    public class DataSourceConfig {
    
    
        private static Logger logger = LoggerFactory.getLogger(DataSourceConfig.class);
    
        @Autowired
        private Environment env;
    
        /**
         *  构造多数据源连接池
         */
        @Bean
        @Primary
        public DynamicDataSource dynamicDataSource() throws SQLException{
    
            Map<Object,Object> druidDataSourceMap = new ConcurrentHashMap<>();
            DruidDataSource dataSource1 = new DruidDataSource();
            dataSource.setUrl("jdbc:mysql:///test1");
            dataSource.setDriverClassName("com.mysql.jdbc.Driver");
            dataSource.setUsername("root");
            dataSource.setPassword("xxxxx");
            
            DruidDataSource dataSource2 = new DruidDataSource();
            dataSource2.setUrl("jdbc:mysql:///test2");
            dataSource2.setDriverClassName("com.mysql.jdbc.Driver");
            dataSource2.setUsername("root");
            dataSource2.setPassword("xxxxx");
            
            //key 值对应enum里的名称
            druidDataSourceMap.put(DatabaseType.mysql1,dataSource1);
            druidDataSourceMap.put(DatabaseType.mysql2,dataSource2);        
    
            DynamicDataSource dataSource = new DynamicDataSource();
            // 该方法是AbstractRoutingDataSource的方法
            dataSource.setTargetDataSources(druidDataSourceMap);
         
            // 默认使用的datasource
            dataSource.setDefaultTargetDataSource(dataSource1);
            return dataSource;
        }
    
        @Bean
        public SqlSessionFactory sqlSessionFactory(DynamicDataSource dynamicDataSource) throws Exception {
            SqlSessionFactoryBean sessionFactoryBean = new SqlSessionFactoryBean();
            sessionFactoryBean.setDataSource(dynamicDataSource);
            sessionFactoryBean.setTypeAliasesPackage(env.getProperty("mybatis.type-aliases-package"));
            sessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(env.getProperty("mybatis.mapper-locations")));
            return sessionFactoryBean.getObject();
        }
    
        @Bean
        public DataSourceTransactionManager transactionManager(DynamicDataSource dataSource) throws Exception {
            return new DataSourceTransactionManager(dataSource);
        }
    
    }

>  AOP实现切换

@Aspect
    @Order(-10)
    @Component
    public class DynamicDataSourceAspect {
    
        private static Logger logger = LoggerFactory.getLogger(DynamicDataSourceAspect.class);
    
        @Pointcut("@annotation(targetDataSource)")
        public void pointCut(TargetDataSource targetDataSource) {}
    
        /*
         *
         * @Before：在方法执行之前进行执行：
         * @annotation(targetDataSource)：
         * 会拦截注解targetDataSource的方法，否则不拦截;
         */
        @Before("pointCut(targetDataSource)")
        public void doBefore(JoinPoint point,TargetDataSource targetDataSource){
            //获取当前的指定的数据源;
            DatabaseType value = targetDataSource.value();
            //如果不在会使用默认的。
            if (targetDataSource.value()==null){
                //找到的话，那么设置到动态数据源上下文中。
                DatabaseContext.setDatabaseType(targetDataSource.value());
            }
        }
    
        /**
         * 清理
         */
        @After("pointCut(targetDataSource)")
        public void after(TargetDataSource targetDataSource){
             DatabaseContextHolder.clearDBKey();
        }
    
    }

>  测试

@RestController
    @RequestMapping("/test")
    public class TestController {
    
        //在访问方法上加入注解即可
    
        @TargetDataSource(DatabaseType.mysql1)
        @GetMapping("/test1")
        public String test1(){
            //会调用 test1数据库
        }
        
        @TargetDataSource(DatabaseType.mysql2)
        @GetMapping("/test2")
        public String test2(){
            //会调用 test2数据库
        }
    }

以上就是了