去重列表对象（根据对象字段）

一 实体类

@Data
@AllArgsConstructor
public class ChannalRobotDTO {

   /**
    * 机器人配置id
    */
   private String robotId;

   /**
    * 城市code
    */
   private String cityCode;

   /**
    * 保司code
    */
   private String companyCode;

   /**
    * 机器人配置名
    */
   private String name;

   /**
    * 重写equals和hashCode完成散列存储去重
    */
   public boolean equals(Object obj){
       ChannalRobotDTO c=(ChannalRobotDTO) obj;
       return companyCode.equals(c.companyCode);
   }

   public int hashCode(){
       String str=companyCode;
       return str.hashCode();
   }
}

二 测试

public class RemovalDemo {
   public static void main(String[] args) {
       List<ChannalRobotDTO> list=new ArrayList<>();
       list.add(new ChannalRobotDTO("1111","1001","TTC","建行"));
       list.add(new ChannalRobotDTO("2222","1002","MIT","建行"));
       list.add(new ChannalRobotDTO("3333","1003","TTC","建行"));
       list.add(new ChannalRobotDTO("4444","1004","MIT","建行"));
       list.add(new ChannalRobotDTO("5555","1005","TTC","建行"));
       /**
        * 对象去重（根据companyCode去重）
        */
       Set<ChannalRobotDTO> set=new HashSet<>(list);
       List<ChannalRobotDTO> dtoList=new ArrayList<>(set);
       System.out.println(dtoList);
       /**
        * 去重结果
        * [ChannalRobotDTO(robotId=1111, cityCode=1001, companyCode=TTC, name=建行),
        * ChannalRobotDTO(robotId=2222, cityCode=1002, companyCode=MIT, name=建行)]
        */
   }
}