java8 把List<Object> 根据某字段去重

悠悠 2021-12-03 16:23 373阅读 0赞

import java.util.ArrayList;
    import java.util.List;
    import org.apache.shiro.SecurityUtils;
    import org.apache.shiro.subject.Subject;
    import java.util.*;
    import java.util.stream.Collectors;
    
    import static java.util.Comparator.comparing;
    import static java.util.Comparator.comparingLong;
    import static java.util.stream.Collectors.collectingAndThen;
    import static java.util.stream.Collectors.toCollection;

1   public static void main(String[] args) {
     2     Milk milk0=new Milk(0,"123456");
     3     Milk milk1=new Milk(1,"123476");
     4     Milk milk2=new Milk(0,"876433");
     5     List<Milk> list=new ArrayList<>();
     6     list.add(milk0);
     7     list.add(milk1);
     8     list.add(milk2);
     9     //去重
    10     List<Milk> uniqueMilk = list.stream().collect(
    11         collectingAndThen(
    12             toCollection(() -> new TreeSet<>(comparing(n->n.getKey()))),ArrayList::new)
    13     );
    14 
    15     for (Milk m:uniqueMilk) {
    16       System.out.println(m.toString());
    17     }
    18 
    19   }

public class Milk {
      private Integer key;
      private String value;
    
      public Milk(Integer key, String value) {
        this.key = key;
        this.value = value;
      }
    
      public Integer getKey() {
        return key;
      }
    
      public void setKey(Integer key) {
        this.key = key;
      }
    
      public String getValue() {
        return value;
      }
    
      public void setValue(String value) {
        this.value = value;
      }
    
      @Override
      public String toString() {
        return "Milk{" + "key=" + key + ", value='" + value + '\'' + '}';
      }
    }

转载于:https://www.cnblogs.com/qq1141100952com/p/11197120.html