public class Student {private String name;private int chinese;private int math;private int english;public Student() {super();}public Student(String name, int chinese, int math, int english) {this.name = name;this.chinese = chinese;this.math = math;this.english = english;}public String getName() {return name;}public void setName(String name) {this.name = name;}public int getChinese() {return chinese;}public void setChinese(int chinese) {this.chinese = chinese;}public int getMath() {return math;}public void setMath(int math) {this.math = math;}public int getEnglish() {return english;}public void setEnglish(int english) {this.english = english;}public int getTotal(){return (this.chinese + this.math + this.english);}@Overridepublic String toString() {return "Student{" +"name='" + name + '\'' +", chinese=" + chinese +", math=" + math +", english=" + english +'}';}
}

import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Comparator;
import java.util.TreeSet;public class Demo {public static void main(String[] args) throws IOException {//创建5个学生对象Student s1 = new Student("孙悟空",80,80,80);Student s2 = new Student("猪八戒",90,90,90);Student s3 = new Student("玉皇大帝",100,100,100);Student s4 = new Student("嫦娥",100,100,100);Student s5 = new Student("白骨精",90,80,100);//按照总分从高到低存入TreeSetTreeSet<Student> set = new TreeSet<>(new Comparator<Student>() {@Overridepublic int compare(Student s1, Student s2) {int cmp1 =   s2.getTotal() - s1.getTotal();//总分从高到低排序int cmp2 = cmp1 == 0 ? s2.getName().compareTo(s1.getName()) : cmp1;//保证可以出现总分相同但是名字不同的学生return cmp2;}});//将学生信息存入集合
        set.add(s1);set.add(s2);set.add(s3);set.add(s4);set.add(s5);//3.遍历集合并写入文件BufferedWriter writer = new BufferedWriter(new FileWriter("Day27_Thread01\\student.txt"));for (Student s :set) {StringBuilder sb = new StringBuilder("姓名：" + s.getName()  + ", 语文成绩：" + s.getChinese() +", 数学成绩：" + s.getMath() + ", 英语成绩：" + s.getEnglish());writer.write(sb.toString());writer.newLine();writer.flush();}writer.close();}
}

import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Comparator;
import java.util.Scanner;
import java.util.TreeSet;public class Demo2 {public static void main(String[] args) throws IOException {//创建TreeSet集合TreeSet<Student> set = new TreeSet<>(new Comparator<Student>() {@Overridepublic int compare(Student s1, Student s2) {int cmp1 =   s2.getTotal() - s1.getTotal();int cmp2 = cmp1 == 0 ? s2.getName().compareTo(s1.getName()) : cmp1;return cmp2;}});for (int i = 0;i < 5;i++){//输入学生信息Scanner sc = new Scanner(System.in);System.out.println("请输入学生的姓名：");String name = sc.nextLine();System.out.println("请输入该学生的语文成绩：");int chinese = sc.nextInt();System.out.println("请输入该学生的数学成绩：");int math = sc.nextInt();System.out.println("请输入该学生的英语成绩：");int english = sc.nextInt();//创建学生对象并录入信息Student s = new Student();s.setName(name);s.setChinese(chinese);s.setMath(math);s.setEnglish(english);//将学生添加到集合里
            set.add(s);}//3.遍历集合并写入文件BufferedWriter writer = new BufferedWriter(new FileWriter("Day27_Thread01\\student.txt"));for (Student s :set) {StringBuilder sb = new StringBuilder("姓名：" + s.getName()  + ", 语文成绩：" + s.getChinese() +", 数学成绩：" + s.getMath() + ", 英语成绩：" + s.getEnglish());writer.write(sb.toString());writer.newLine();writer.flush();}//关闭资源
        writer.close();}
}