Java 学生系统代码

### 回答1：
由于您并没有说明具体的学生系统要求，这里提供一份基本的学生信息管理系统代码供参考：

import java.util.Scanner;

public class StudentSystem {

    // 定义学生类
    private static class Student {
        private String name;
        private String id;
        private int age;

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

        public String getName() {
            return name;
        }

        public String getId() {
            return id;
        }

        public int getAge() {
            return age;
        }
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int size = 10; // 学生数组大小，可以根据需要修改
        Student[] students = new Student[size]; // 学生数组

        // 主菜单
        System.out.println("欢迎使用学生信息管理系统！");
        while (true) {
            System.out.println("请选择操作：");
            System.out.println("1. 添加学生信息");
            System.out.println("2. 查看学生信息");
            System.out.println("3. 修改学生信息");
            System.out.println("4. 删除学生信息");
            System.out.println("5. 退出系统");

            int choice = scanner.nextInt();
            switch (choice) {
                case 1:
                    addStudent(students);
                    break;
                case 2:
                    viewStudents(students);
                    break;
                case 3:
                    modifyStudent(students);
                    break;
                case 4:
                    deleteStudent(students);
                    break;
                case 5:
                    System.out.println("谢谢使用！");
                    System.exit(0);
                default:
                    System.out.println("无效的选项！");
            }
        }
    }

    // 添加学生
    private static void addStudent(Student[] students) {
        Scanner scanner = new Scanner(System.in);

        for (int i = 0; i < students.length; i++) {
            if (students[i] == null) {
                System.out.println("请输入学生姓名：");
                String name = scanner.next();

                System.out.println("请输入学生学号：");
                String id = scanner.next();

                System.out.println("请输入学生年龄：");
                int age = scanner.nextInt();

                Student student = new Student(name, id, age);
                students[i] = student;

                System.out.println("添加成功！");
                break;
            }
        }
    }

    // 查看学生列表
    private static void viewStudents(Student[] students) {
        boolean hasStudent = false;
        for (Student student : students) {
            if (student != null) {
                hasStudent = true;
                System.out.println("姓名：" + student.getName() + "，学号：" + student.getId() + "，年龄：" + student.getAge());
            }
        }
        if (!hasStudent) {
            System.out.println("目前没有学生信息！");
        }
    }

    // 修改学生信息
    private static void modifyStudent(Student[] students) {
        Scanner scanner = new Scanner(System.in);

        System.out.println("请输入要修改的学生学号：");
        String id = scanner.next();

        Student student = findStudentById(students, id);
        if (student != null) {
            System.out.println("请输入学生姓名（留空不修改）：");
            String name = scanner.next();
            if (!name.isEmpty()) {
                student.name = name;
            }

            System.out.println("请输入学生年龄（留空不修改）：");
            String ageStr = scanner.next();
            if (!ageStr.isEmpty()) {
                int age = Integer.parseInt(ageStr);
                student.age = age;
            }

            System.out.println("修改成功！");
        } else {
            System.out.println("找不到该学生！");
        }
    }

    // 删除学生信息
    private static void deleteStudent(Student[] students) {
        Scanner scanner = new Scanner(System.in);

        System.out.println("请输入要删除的学生学号：");
        String id = scanner.next();

        Student student = findStudentById(students, id);
        if (student != null) {
            for (int i = 0; i < students.length; i++) {
                if (students[i] == student) {
                    students[i] = null;
                    System.out.println("删除成功！");
                    break;
                }
            }
        } else {
            System.out.println("找不到该学生！");
        }
    }

    // 根据学号查找学生
    private static Student findStudentById(Student[] students, String id) {
        for (Student student : students) {
            if (student != null && student.getId().equals(id)) {
                return student;
            }
        }
        return null;
    }
}

### 回答2：
Java 学生系统代码可以有很多种实现方式，以下是一个简单的示例：

import java.util.Scanner;

public class StudentSystem {
    private Student[] students;
    private int count;

    public StudentSystem(int size) {
        students = new Student[size];
        count = 0;
    }

    public void addStudent(Student student) {
        if (count < students.length) {
            students[count] = student;
            count++;
            System.out.println("学生添加成功！");
        } else {
            System.out.println("学生系统已满，无法添加新学生！");
        }
    }

    public void searchStudent(String name) {
        boolean found = false;
        for (int i = 0; i < count; i++) {
            if (students[i].getName().equals(name)) {
                System.out.println("学生信息：" + students[i]);
                found = true;
                break;
            }
        }
        if (!found) {
            System.out.println("查无此人！");
        }
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        StudentSystem studentSystem = new StudentSystem(10);

        while (true) {
            System.out.println("请选择操作：");
            System.out.println("1. 添加学生");
            System.out.println("2. 查找学生");
            System.out.println("3. 退出");

            int choice = scanner.nextInt();
            scanner.nextLine();

            switch (choice) {
                case 1:
                    System.out.print("请输入学生姓名：");
                    String name = scanner.nextLine();
                    System.out.print("请输入学生年龄：");
                    int age = scanner.nextInt();

                    Student student = new Student(name, age);
                    studentSystem.addStudent(student);
                    break;
                case 2:
                    System.out.print("请输入要查找的学生姓名：");
                    String searchName = scanner.nextLine();
                    studentSystem.searchStudent(searchName);
                    break;
                case 3:
                    System.exit(0);
                    break;
                default:
                    System.out.println("无效的选项！");
            }
        }
    }
}

class Student {
    private String name;
    private int age;

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

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }

    @Override
    public String toString() {
        return "姓名：" + name + "，年龄：" + age;
    }
}

这段代码实现了一个简单的学生系统。使用 `StudentSystem` 类来管理学生对象的添加和查找操作，`Student` 类表示一个学生对象，其中包含姓名和年龄信息。在 `main` 方法中，通过用户输入选择操作类型，并根据选择执行相应的功能。用户可以选择添加学生或查找学生，程序会根据用户输入的信息进行相应的操作。