补充Student类和StudentManage类，实现学生信息录入、排序、按学号查询学生（如果查询的学生不存在，输出提示信息），

好的，这里提供一个简单的示例代码：

//定义Student类
public class Student implements Comparable<Student> {
    private String id;
    private String name;
    private int age;

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

    public String getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }

    @Override
    public int compareTo(Student o) {
        return this.id.compareTo(o.getId());
    }
}

//定义StudentManage类
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public class StudentManage {
    private List<Student> students;

    public StudentManage() {
        students = new ArrayList<>();
    }

    public void addStudent(Student student) {
        students.add(student);
    }

    public void sortById() {
        Collections.sort(students);
    }

    public Student findById(String id) {
        for (Student student : students) {
            if (student.getId().equals(id)) {
                return student;
            }
        }
        System.out.println("查询的学生不存在！");
        return null;
    }
}

使用示例：

public class Test {
    public static void main(String[] args) {
        StudentManage studentManage = new StudentManage();

        //添加学生信息
        studentManage.addStudent(new Student("001", "张三", 20));
        studentManage.addStudent(new Student("003", "李四", 21));
        studentManage.addStudent(new Student("002", "王五", 19));

        //按学号排序
        studentManage.sortById();

        //按学号查询学生
        Student student = studentManage.findById("002");
        if (student != null) {
            System.out.println("查询结果：" + student.getName() + "，" + student.getAge() + "岁");
        }
    }
}

输出结果：

查询结果：王五，19岁