集合-TreeSet-Comparator

 package com.bjpowernode.tree2;

 public class Student {

     private String name;
     private int age;
     public String getName() {
         return name;
     }
     public void setName(String name) {
         this.name = name;
     }
     public int getAge() {
         return age;
     }
     public void setAge(int age) {
         this.age = age;
     }
     public Student(String name, int age) {
         super();
         this.name = name;
         this.age = age;
     }
     @Override
     public String toString() {
         return "Student [name=" + name + ", age=" + age + "]";
     }

 }

 package com.bjpowernode.tree2;

 import java.util.Comparator;

 public class StudentComparator implements Comparator<Student> {

     @Override
     public int compare(Student stu1, Student stu2) {

         if (stu1.getAge()==stu2.getAge()) {
             return stu1.getName().compareTo(stu2.getName());
         }
         return stu1.getAge()-stu2.getAge();
     }

 }

 package com.bjpowernode.tree2;

 import java.util.Set;
 import java.util.TreeSet;

 public class TreeSet1 {

     public static void main(String[] args) {

         StudentComparator studentComparator=new StudentComparator();
         Set<Student> set=new TreeSet<>(studentComparator);
         Student stu1=new Student("张三", 66);
         Student stu2=new Student("lisi", 23);
         Student stu3=new Student("刘能", 45);
         Student stu4=new Student("赵本山", 62);
         Student stu5=new Student("赵本山", 62);
         Student stu6=new Student("abc", 45);
         set.add(stu1);
         set.add(stu2);
         set.add(stu3);
         set.add(stu4);
         set.add(stu5);
         set.add(stu6);
 //        for (Student student : set) {
 //            System.out.println(student);
 //        }
         System.out.println("姓名\t年龄");
 //        System.out.println("姓名"+"\t"+"年龄");
         for (Student student : set) {
             System.out.println(student.getName()+"\t"+student.getAge());
         }
     }

 }