Question

我已经合并了上面的列表，但需要根据id参数对其进行排序。如何以最简单和最佳的方式做到这一点？我最初合并了2个用户，现在我想根据其ID对他们进行排序，然后显示结果。有任何想法吗？

  import java.io.*;
    import java.util.*;


/*
 * To execute Java, please define "static void main" on a class
 * named Solution.
 *
 * If you need more classes, simply define them inline.
 */

class Employee {
  public String name;
  public int id;

  Employee(String name, int id) {
    this.name = name;
    this.id = id;
  }


  public String toString() {
    return "<name: " + this.name + ", id: " + this.id + ">";
  }
}

class Person {
  public String name;
  public int id;

  Person(String name, int id) {
    this.name = name;
    this.id = id;
  }

  public String toString() {
    return "<name: " + this.name + ", id: " + this.id + ">";
  }
}


public class Solution {
  public static void main(String[] args) {
    List<Employee> employee = generateEmployees();
    List<Person> persons = generatePersons();


ArrayList<Object> merged = new ArrayList<Object>(employee);
        merged.addAll(person);
        System.out.println("merged:"+merged +"\n");


   for(int i=0;i<users.size();i++){
        if(person.get(i).id<=5){
        System.out.println("UserName:"+person.get(i).name+"\n");
        }
      }
     for(int i=0;i<employee.size();i++){
       if(employee.get(i).id<=5){
        System.out.println("DesignerName:"+employee.get(i).name+"\n");
        }
      }

});

  }

提前谢谢！我已经看过几种在线排序方法，但无法使用这是最好的使用方法。只想在排序后显示结果

Answer 1

User和Designer必须从同一类扩展。（或Designer extand user）。
然后创建一个比较器（javadoc），然后使用merged.sort (myComparator)（javadoc）

[ EDIT ]

class MyComparator implements Comparator<User> {
    @Override
    public int compare(User o1, User o2) {
        return Integer.compare(o1.id, o2.id);
    }
}


public class User {
    public String name;
    public int id;

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

    public String toString() {
        return "<name: " + this.name + ", id: " + this.id + ">";
    }

}



public class Designer extends User{
    Designer(String enter code herename, int id) {
        super(name, id);
    }
}


public class Solution {
    public static void main(String[] args) {
        ...

        ArrayList<User> merged = new ArrayList<User>(designers);
        merged.addAll(users);
        merged.sort(new MyComparator());
...
    }
}

Answer 2

假定您有一个名为User的{{1}}列表：

users

如何按已合并ID的2个列表的元素排序？

2 个答案: