实现MyBatis查询返回值Map（String,Object）

﹏ヽ暗。殇╰゛Y 2022-05-20 01:43 278阅读 0赞

今天有一个需求需要MyBatis返回值格式为Map<String,bean>,找了一些帖子和资料，自己研究半天终于解决。

题目不让加<> 符号

## 重写org.apache.ibatis.session 中ResultHandler接口 ##

public class FblMapResultHandler implements ResultHandler {  
    	@SuppressWarnings("rawtypes") 
        private final  Map<String, DeviceBean> mappedResults = new HashMap<String, DeviceBean>() ;
    	@SuppressWarnings("unchecked")
        @Override  
        public void handleResult(ResultContext context) {  
            @SuppressWarnings("rawtypes")  
            Map<String,Object> paramap=new HashMap<String,Object>();
            DeviceBean deviceBean =  (DeviceBean) context.getResultObject();
            String code = deviceBean.getCode();
            mappedResults.put(code, deviceBean);       
        }  
        public  Map<String, DeviceBean> getMappedResults() {    
            return mappedResults;    
        }    
    }

## Service ##

public Map<String, DeviceBean> getDeviceCollectStateIdByBean(Map<String, Object> parameter)

## ServiceImpl    ##

@Override
        public Map<String, DeviceBean> getDeviceCollectStateIdByBean(Map<String, Object> parameter) {
        logger.info("DeviceServiceImpl{}==>getDeviceCollectStateIdByBean()");
        return deviceDao.getDeviceCollectStateIdByBean(parameter);
        }

## Dao  ##

public Map<String, DeviceBean> getDeviceCollectStateIdByBean(Map<String, Object> parameter);

## DaoImpl ##

private final String namespace = "com..................Mapper.";
    	public String sqlId(String method) {
    		return namespace + method;
    	}
    	@Override	
    	public Map<String, DeviceBean> getDeviceCollectStateIdByBean(Map<String, Object> parameter) {
    		logger.info("DeviceDaoImpl{}==>getDeviceCollectStateIdByBean()");	
    	      FblMapResultHandler fbl = new FblMapResultHandler();  
    	       getWriteSession().select(sqlId("getDeviceCollectStateIdByBean"),parameter,fbl);  
    	       @SuppressWarnings("rawtypes")  
    	       Map<String, DeviceBean> map =fbl.getMappedResults();  
    	       return map;  	       
    	}

## Mapper ##

<select id="getDeviceCollectStateIdByBean" resultType="com.....DeviceBean" parameterType="map" >
    	    select 
    	    d.id as id, d.group_id as groupId,d.farm_id as farmId, d.house_id as houseId, d.code
    	    from t_device d
    	    WHERE  d.del_flag = '0' and d.code in 
    	        <foreach item="item" index="index" collection="codelist" open="(" separator="," close=")">  
    		  #{item}  
    		</foreach>
    	</select>

## 测试打印结果 ##

List<String>  codeList =new ArrayList<String>(); 
            codeList.add("b827ebee9322");
            codeList.add("111");
            codeList.add("1111");
            Map<String,Object> paramap=new HashMap<String,Object>();
            paramap.put("codelist", codeList); 
    	Map<String, DeviceBean> res = deviceService.getDeviceCollectStateIdByBean(paramap);
    	System.out.println(res);
    	String test = res.get("111").getFarmName();
    	System.out.println(test);

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[70]: /images/20220520/25488e7a37dd4cc181d7d70e47fd7192.png