java实现对象去重，实现内存分页

//第一种方式

package com.example.springbootfastdfs.controller;

/**

• @Auther: ly

• @Date: 2019-2-27 16:52

• @Description:
  */
  public class User {

  private String id;
  private String name;

  public User(String id, String name) {
  this.id = id;
  this.name = name;
  }

  public String getId() {
  return id;
  }

  public void setId(String id) {
  this.id = id;
  }

  public String getName() {
  return name;
  }

  public void setName(String name) {
  this.name = name;
  }
  }
  ackage com.example.springbootfastdfs.controller;

import java.util.*;
import java.util.stream.Collectors;

/**

• @Auther: ly

• @Date: 2019-2-27 16:18

• @Description:
  */
  public class Test2 {

  public static List removeDuplicateCase(List list){
  Set treeSet = new TreeSet<>(new Comparator() {

       @Override
       public int compare(User o1, User o2) {
           String str1 = o1.getId();
           String str2 = o2.getId();
           //根据多属性进行对象去重
           int compareTo = str1.compareTo(str2);
           return compareTo;
       }
   });
   treeSet.addAll(list);
   return new ArrayList<>(treeSet);
  

  }
  public static void main(String[] args) {
  List userList = new ArrayList<>();
  userList.add(new User(“1”,“大海ia”));
  userList.add(new User(“1”,“大海”));
  userList.add(new User(“2”,“大海ia”));
  userList.add(new User(“3”,“大海ia”));
  List users =removeDuplicateCase(userList);
  for(User ss:users){
  System.out.println(ss.getId()+":::"+ ss.getName());
  }

  }
  }
  //第二种
  package com.example.springbootfastdfs.controller;

/**

• @Auther: ly

• @Date: 2019-2-27 16:52

• @Description:
  */
  public class User {

  private String id;
  private String name;

  public User(String id, String name) {
  this.id = id;
  this.name = name;
  }

  public String getId() {
  return id;
  }

  public void setId(String id) {
  this.id = id;
  }

  public String getName() {
  return name;
  }

  public void setName(String name) {
  this.name = name;
  }

  @Override
  public boolean equals(Object obj) {
  User s=(User)obj;
  return id.equals(s.id);
  }
  @Override
  public int hashCode() {
  String in = id ;
  return in.hashCode();
  }

}

package com.example.springbootfastdfs.controller;

import java.util.*;
import java.util.stream.Collectors;

/**

• @Auther: ly

• @Date: 2019-2-27 16:18

• @Description:
  */
  public class Test2 {

  public static List removeDuplicateCase(List list){
  Set treeSet = new TreeSet<>(new Comparator() {

       @Override
       public int compare(User o1, User o2) {
           String str1 = o1.getId();
           String str2 = o2.getId();
           //根据多属性进行对象去重
           int compareTo = str1.compareTo(str2);
           return compareTo;
       }
   });
   treeSet.addAll(list);
   return new ArrayList<>(treeSet);
  

  }
  public static void main(String[] args) {
  List userList = new ArrayList<>();
  userList.add(new User(“1”,“大海ia”));
  userList.add(new User(“1”,“大海”));
  userList.add(new User(“2”,“大海ia”));
  userList.add(new User(“3”,“大海ia”));
  // List users =removeDuplicateCase(userList);
  Set set = new HashSet<>();
  set.addAll(userList);
  for(User ss:set){
  System.out.println(ss.getId()+":::"+ ss.getName());
  }

  }
  }