java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to xxx实体类

最新推荐文章于 2023-09-19 16:54:04 发布

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最新推荐文章于 2023-09-19 16:54:04 发布

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分类专栏： java 文章标签： java

本文链接：https://blog.youkuaiyun.com/fortunate_leixin/article/details/126828838

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前端封装的json格式的数据，后台接收的参数的时候直接使用的Map去接收的，导致再对数据进行forearch操作的时候报错，提示信息为

java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to com.ruoyi.systemTestTaskManager.domain.HollySubTaskDevices

public int updateSubTaskInfo(Map<String, Object> confirmParms) {
     List<HollySubTaskDevices> toolDeploys = (ArrayList<HollySubTaskDevices>) ;
     confirmParms.get("devices");
        if (toolDeploys.size() != 0) {
            toolDeploys.forEach(obj -> obj.setRelationId(IdUtils.simpleUUID()));
            toolDeploys.forEach(obj -> obj.setDelFlag("0"));
            hollySubTaskMapper.updateSubTaskDevices(toolDeploys);
            hollySubTaskMapper.insertSubTaskDevices(toolDeploys);
        }
}

解决方案1：

ObjectMapper mapper = new ObjectMapper();
 List<HollySubTaskDevices> list1 = (List<HollySubTaskDevices>) confirmParms.get("devices");
List<HollySubTaskDevices> devices= mapper.convertValue(list1, new TypeReference<List<HollySubTaskDevices>>(){});

引入包的路径

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.core.type.TypeReference;

结果：
在这里插入图片描述
解决方案2：使用流的方式转换

解决方案3：后台定义一个dto 里面的数据格式与前端传递的格式一致。controller层接收时用这个dto 接收

   /**
     * @param confirmParms
     * @return {@link AjaxResult}
     * @date 2022/9/9 15:17
     * @author leixin
     * @Description ////
     */
    @PostMapping("/updateSubTaskInfo")
    public AjaxResult updateSubTaskInfo(@RequestBody ConfirmParmsDTO confirmParms) {

        return AjaxResult.success( hollySubTaskService.updateSubTaskInfo(confirmParms));
    }

ConfirmParmsDTO :

@Data
public class ConfirmParmsDTO {
    private List<HollySubTaskDevices> devices;
    private  List<HollySubTaskToolDeploy> toolDeploy;
    private List<HollySubTaskToolConfig> toolConfig;
    private Map<String,Object> topoData;
}

server层处理

 public int updateSubTaskInfo(ConfirmParmsDTO confirmParms) {
        List<HollySubTaskDevices> toolDeploys = confirmParms.getDevices();
        List<HollySubTaskToolConfig> hollySubTaskToolConfigs =  confirmParms.getToolConfig();
        List<HollySubTaskToolDeploy> hollySubTaskToolDeploys = confirmParms.getToolDeploy();
        Map<String, Object> topoData = confirmParms.getTopoData();
        if (toolDeploys.size() != 0) {
            /** 关联Id*/
            toolDeploys.forEach(obj -> obj.setRelationId(IdUtils.simpleUUID()));
            toolDeploys.forEach(obj -> obj.setDelFlag("0"));
            hollySubTaskMapper.updateSubTaskDevices(toolDeploys);
            hollySubTaskMapper.insertSubTaskDevices(toolDeploys);
        }
        if (hollySubTaskToolConfigs.size() != 0) {
            hollySubTaskToolConfigs.forEach(obj -> obj.setRelationId(IdUtils.simpleUUID()));
            hollySubTaskToolConfigs.forEach(obj -> obj.setDelFlag("0"));
            hollySubTaskMapper.updateSubTaskToolConfigs(hollySubTaskToolConfigs);
            hollySubTaskMapper.insertHollySubTaskToolConfigs(hollySubTaskToolConfigs);
        }
        if (hollySubTaskToolDeploys.size() != 0) {
            hollySubTaskToolDeploys.forEach(obj -> obj.setRelationId(IdUtils.simpleUUID()));
            hollySubTaskToolDeploys.forEach(obj -> obj.setDelFlag("0"));
            hollySubTaskMapper.updateHollySubTaskToolDeploys(hollySubTaskToolDeploys);
            hollySubTaskMapper.insertHollySubTaskToolDeploys(hollySubTaskToolDeploys);
        }
         String subTaskId = String.valueOf(topoData.get("subTaskId"));
         String jsonStr = new JSONObject(topoData).toString();
         hollySubTaskMapper.updateTopoData(subTaskId,jsonStr );
        return 0;
    }

描述有误的地方欢迎大家指正，大家有问题可加v 876942434。一起进步~