package set;import java.util.ArrayList;import java.util.Collections;import java.util.Comparator;import java.util.List;public class SetSort {    public static void main(String[] args) {        // TODO Auto-generated method stub        SortModel sortModel1 = new SortModel();        sortModel1.setAge(1);        sortModel1.setName("a");        SortModel sortModel2 = new SortModel();        sortModel2.setAge(2);        sortModel2.setName("b");                List
     
       sortModels = new ArrayList<>();        sortModels.add(sortModel2);        sortModels.add(sortModel1);                 List
      
        list = new ArrayList<>();         list.addAll(sortModels);                  Collections.sort(sortModels, new Comparator
       
        () {                @Override                public int compare(SortModel b1, SortModel b2) {                    return b2.getAge() - b1.getAge();                }            });    }}package set;public class SortModel {    private int age;        private String name;    public int getAge() {        return age;    }    public void setAge(int age) {        this.age = age;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }        }