TreeSet使用比较器Comparator排序

package myTreeSetDemo;

public class Student {
    private String name;
    private int age;

    public Student() {
    }

    public Student(String name, int age) {
        this.name = name;
        this.age = 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;
    }
}

package myTreeSetDemo;

import java.util.Comparator;
import java.util.TreeSet;

public class TreeSetComparatorDemo {
    public static void main(String[] args) {
    	//使用匿名内部类
        TreeSet<Student> treeSet = new TreeSet<Student>(new Comparator<Student>() {
            @Override
            public int compare(Student s1, Student s2) {
                //先比较年龄
                int num = s1.getAge() - s2.getAge();
                //若年龄相等，再比较姓名
                int num2 = (num == 0 ? s1.getName().compareTo(s2.getName()) : num);
                return num2;
            }
        });

        Student s1 = new Student("xiaozhao", 19);
        Student s2 = new Student("xiaoli", 20);
        Student s3 = new Student("xiaowang", 18);
        Student s4 = new Student("xiaoma", 23);

        Student s5 = new Student("xiaohua", 20);
        Student s6 = new Student("xiaohua", 20);

        treeSet.add(s1);
        treeSet.add(s2);
        treeSet.add(s3);
        treeSet.add(s4);

        treeSet.add(s5);
        treeSet.add(s6);

        for (Student s : treeSet) {
            System.out.println(s.getName() + "," + s.getAge());
        }
    }
}

结果：