4、使用TreeMap集合实现对存入10位学生的Java成绩从小到大输出；学生类定义参考第3题，在第3题学生类的基础上增加Java成绩属性。

以下是使用TreeMap集合实现对存入10位学生的Java成绩从小到大输出的Java代码：

import java.util.*;

public class Student implements Comparable<Student> {
    private String name;
    private int age;
    private int javaScore;

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

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }

    public int getJavaScore() {
        return javaScore;
    }

    @Override
    public int compareTo(Student s) {
        return Integer.compare(this.javaScore, s.javaScore);
    }

    public static void main(String[] args) {
        Map<Student, Integer> map = new TreeMap<>();
        map.put(new Student("Tom", 18, 90), 1);
        map.put(new Student("Jerry", 19, 80), 2);
        map.put(new Student("Mike", 20, 70), 3);
        map.put(new Student("John", 21, 60), 4);
        map.put(new Student("Lucy", 22, 50), 5);
        map.put(new Student("Lily", 23, 40), 6);
        map.put(new Student("Bob", 24, 30), 7);
        map.put(new Student("Alice", 25, 20), 8);
        map.put(new Student("David", 26, 10), 9);
        map.put(new Student("Frank", 27, 0), 10);

        for (Map.Entry<Student, Integer> entry : map.entrySet()) {
            System.out.println(entry.getKey().getName() + " " + entry.getKey().getAge() + " " + entry.getKey().getJavaScore());
        }
    }
}