java编写学生管理系统

下面是一个简单的学生管理系统的Java代码示例：

import java.util.ArrayList;
import java.util.Scanner;

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

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

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }

    public String getId() {
        return id;
    }

    public void printInfo() {
        System.out.println("Name: " + name + " Age: " + age + " ID: " + id);
    }
}

public class StudentManagementSystem {
    private ArrayList<Student> students;

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

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

    public void removeStudent(Student student) {
        students.remove(student);
    }

    public void printAllStudents() {
        for (Student s : students) {
            s.printInfo();
        }
    }

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        StudentManagementSystem sms = new StudentManagementSystem();

        while (true) {
            System.out.println("Enter 1 to add a student, 2 to remove a student, 3 to print all students, or 4 to exit:");
            int choice = sc.nextInt();

            if (choice == 1) {
                System.out.println("Enter student name:");
                String name = sc.next();
                System.out.println("Enter student age:");
                int age = sc.nextInt();
                System.out.println("Enter student ID:");
                String id = sc.next();
                Student student = new Student(name, age, id);
                sms.addStudent(student);
                System.out.println("Student added.");
            } else if (choice == 2) {
                System.out.println("Enter student ID to remove:");
                String id = sc.next();
                Student studentToRemove = null;
                for (Student s : sms.students) {
                    if (s.getId().equals(id)) {
                        studentToRemove = s;
                        break;
                    }
                }
                if (studentToRemove != null) {
                    sms.removeStudent(studentToRemove);
                    System.out.println("Student removed.");
                } else {
                    System.out.println("Student not found.");
                }
            } else if (choice == 3) {
                sms.printAllStudents();
            } else if (choice == 4) {
                break;
            } else {
                System.out.println("Invalid choice.");
            }
        }

        sc.close();
    }
}

这个程序定义了两个类：`Student` 和 `StudentManagementSystem`。`Student` 类表示一个学生，包括姓名、年龄和学号等信息，以及打印信息的方法。`StudentManagementSystem` 类表示一个学生管理系统，包括添加学生、删除学生和打印所有学生的方法，以及一个 `main` 方法来运行整个程序。

在 `main` 方法中，使用一个死循环来不断读取用户输入的选项。根据用户的选择，分别调用 `addStudent`、`removeStudent` 和 `printAllStudents` 方法来添加、删除和打印学生信息。用户可以输入 `4` 来退出循环，结束程序运行。

这只是一个简单的示例，实际的学生管理系统可能需要更多的功能和复杂的实现。