spring boot + mybatis + druid實現多數據源配置

源碼：https://download.csdn.net/download/asd792520/11830815

一、結構目錄

二、添加主要依賴

自行添加mysql或者oracle驅動包

三、多數據源的處理

1、自定義註解以及數據源枚舉

/**
 * Created by qiuzhb on 2019/9/30.
 *
 * @Description 自定義多數據源切換註解
 */
@Target({ ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
public @interface DataSource {

    public DataSourceType value() default DataSourceType.MASTER;
}

/**
 * Created by qiuzhb on 2019/9/30.
 *
 * @Description 數據源
 */
public enum DataSourceType {

    /**
     * 主庫
     */
    MASTER,

    /**
     * 從庫
     */
    SLAVE
}

 

 2、druid配置屬性

/**
 * Created by qiuzhb on 2019/9/30.
 *
 * @Description druid 配置屬性
 */
@Configuration
public class DruidProperties {

    @Value("${spring.datasource.druid.initialSize}")
    private int initialSize;

    @Value("${spring.datasource.druid.minIdle}")
    private int minIdle;

    @Value("${spring.datasource.druid.maxActive}")
    private int maxActive;

    @Value("${spring.datasource.druid.maxWait}")
    private int maxWait;

    @Value("${spring.datasource.druid.timeBetweenEvictionRunsMillis}")
    private int timeBetweenEvictionRunsMillis;

    @Value("${spring.datasource.druid.minEvictableIdleTimeMillis}")
    private int minEvictableIdleTimeMillis;

    @Value("${spring.datasource.druid.maxEvictableIdleTimeMillis}")
    private int maxEvictableIdleTimeMillis;

    @Value("${spring.datasource.druid.validationQuery}")
    private String validationQuery;

    @Value("${spring.datasource.druid.testWhileIdle}")
    private boolean testWhileIdle;

    @Value("${spring.datasource.druid.testOnBorrow}")
    private boolean testOnBorrow;

    @Value("${spring.datasource.druid.testOnReturn}")
    private boolean testOnReturn;

    public DruidDataSource dataSource(DruidDataSource datasource)
    {
        /** 配置初始化大小、最小、最大 */
        datasource.setInitialSize(initialSize);
        datasource.setMaxActive(maxActive);
        datasource.setMinIdle(minIdle);

        /** 配置獲取連接等待超時的時間 */
        datasource.setMaxWait(maxWait);

        /** 配置間隔多久才進行一次檢測，檢測需要關閉的空閒連接，單位是毫秒 */
        datasource.setTimeBetweenEvictionRunsMillis(timeBetweenEvictionRunsMillis);

        /** 配置一個連接在池中最小、最大生存的時間，單位是毫秒 */
        datasource.setMinEvictableIdleTimeMillis(minEvictableIdleTimeMillis);
        datasource.setMaxEvictableIdleTimeMillis(maxEvictableIdleTimeMillis);

        /**
         * 用來檢測連接是否有效的sql，要求是一個查詢語句，常用select 'x'。如果validationQuery爲null，testOnBorrow、testOnReturn、testWhileIdle都不會起作用。
         */
        datasource.setValidationQuery(validationQuery);
        /** 建議配置爲true，不影響性能，並且保證安全性。申請連接的時候檢測，如果空閒時間大於timeBetweenEvictionRunsMillis，執行validationQuery檢測連接是否有效。 */
        datasource.setTestWhileIdle(testWhileIdle);
        /** 申請連接時執行validationQuery檢測連接是否有效，做了這個配置會降低性能。 */
        datasource.setTestOnBorrow(testOnBorrow);
        /** 歸還連接時執行validationQuery檢測連接是否有效，做了這個配置會降低性能。 */
        datasource.setTestOnReturn(testOnReturn);
        return datasource;
    }
}

3、druid 配置多數據源

/**
 * Created by qiuzhb on 2019/9/30.
 *
 * @Description druid 配置多數據源
 */

@Configuration
public class DruidConfig {

    @Bean
    @ConfigurationProperties("spring.datasource.druid.master")
    public DataSource masterDataSource(DruidProperties properties) {
        DruidDataSource build = DruidDataSourceBuilder.create().build();
        return properties.dataSource(build);
    }

    @Bean
    @ConfigurationProperties("spring.datasource.druid.slave")
    @ConditionalOnProperty(prefix = "spring.datasource.druid.slave", name = "enabled", havingValue = "true")
    public DataSource slaveDataSource(DruidProperties properties) {
        DruidDataSource build = DruidDataSourceBuilder.create().build();
        return properties.dataSource(build);
    }

    @Bean(name = "dynamicDataSource")
    @Primary
    public DynamicDataSource dataSource(DataSource masterDataSource, DataSource slaveDataSource)
    {
        Map<Object, Object> targetDataSources = new HashMap<>();
        targetDataSources.put(DataSourceType.MASTER.name(), masterDataSource);
        targetDataSources.put(DataSourceType.SLAVE.name(), slaveDataSource);
        return new DynamicDataSource(masterDataSource, targetDataSources);
    }
}

4、數據源的切換處理

/**
 * Created by qiuzhb on 2019/9/30.
 *
 * @Description 數據源切換處理
 */
@Slf4j
public class DynamicDataSourceContextHolder {

    /**
     * 使用ThreadLocal維護變量，ThreadLoacl爲每個使用該變量的線程提供獨立變量副本
     * 所以每個線程都可以獨立的改變自己的副本，而不影響其他線程對應的副本
     */
    private static final ThreadLocal<String> CONTEXT_HOLDER = new ThreadLocal<>();

    /**
     * 設置數據源變量
     * @param dataSourceType
     */
    public static void setDataSourceType(String dataSourceType) {
        log.info("切換到{}數據源", dataSourceType);
        CONTEXT_HOLDER.set(dataSourceType);
    }

    /**
     * 獲取數據源變量
     */
    public static String getDataSourceType() {
        return CONTEXT_HOLDER.get();
    }

    /**
     * 清楚數據源變量
     */
    public static void clearDataSourceType() {
        CONTEXT_HOLDER.remove();
    }
}

5、動態數據源

/**
 * Created by qiuzhb on 2019/9/30.
 *
 * @Description 動態數據源
 */
public class DynamicDataSource extends AbstractRoutingDataSource {

    public DynamicDataSource(DataSource defaultTargetDataSource, Map<Object, Object> targetDataSources) {
        super.setDefaultTargetDataSource(defaultTargetDataSource);
        super.setTargetDataSources(targetDataSources);
        super.afterPropertiesSet();
    }

    @Override
    protected Object determineCurrentLookupKey() {
        return DynamicDataSourceContextHolder.getDataSourceType();
    }
}

 6、利用aop進行多數據源處理

/**
 * Created by qiuzhb on 2019/9/30.
 *
 * @Description 多數據源處理
 */
@Aspect
@Order(1)
@Component
@Slf4j
public class DataSourceAcpect {

    @Pointcut("@annotation(com.qiuzhb.annotation.DataSource)" +
            "|| @within(com.qiuzhb.annotation.DataSource)")
    public void dsPoincut() {

    }

    @Around("dsPoincut()")
    public Object around(ProceedingJoinPoint point) throws Throwable {
        DataSource dataSource = getDataSource(point);
        if (dataSource != null) {
            DynamicDataSourceContextHolder.setDataSourceType(dataSource.value().name());
        }
        try {
            return point.proceed();
        } finally {
            // 銷燬數據源，在執行方法之後
            DynamicDataSourceContextHolder.clearDataSourceType();
        }

    }

    /**
     * 獲取需要切換的數據源
     * @param joinPoint
     * @return
     */
    public DataSource getDataSource(ProceedingJoinPoint joinPoint) {
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();
        Class<? extends Object> aClass = joinPoint.getTarget().getClass();
        DataSource targetDataSource = aClass.getAnnotation(DataSource.class);
        if (targetDataSource != null ) {
            return targetDataSource;
        } else {
            Method method = signature.getMethod();
            DataSource methodDataSource = method.getAnnotation(DataSource.class);
            return methodDataSource;
        }
    }
}

四、測試

在service類中的方法上打上註解

@DataSource(DataSourceType.SLAVE)
    public int getCount() {
        int count = dao.getCount();
        return count;
    }

 編寫test測試

@Test
    public void dataSourceTest() {
        int count = service.getCount();
        System.out.println(count);
    }

結果：

ps：如有問題，還望不吝賜教！