java实现一个学生管理系统

以下是一个简单的Java学生管理系统的实现：

1. 定义一个Student类，包含以下属性：学号、姓名、性别、年龄、班级、成绩。

public class Student {
    private String id;
    private String name;
    private String gender;
    private int age;
    private String className;
    private double score;

    // 构造方法
    public Student(String id, String name, String gender, int age, String className, double score) {
        this.id = id;
        this.name = name;
        this.gender = gender;
        this.age = age;
        this.className = className;
        this.score = score;
    }

    // getter和setter方法
    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getGender() {
        return gender;
    }

    public void setGender(String gender) {
        this.gender = gender;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getClassName() {
        return className;
    }

    public void setClassName(String className) {
        this.className = className;
    }

    public double getScore() {
        return score;
    }

    public void setScore(double score) {
        this.score = score;
    }
}

2. 定义一个StudentManager类，实现对学生信息的增删改查操作。

import java.util.ArrayList;
import java.util.List;

public class StudentManager {
    private List<Student> students;

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

    // 添加学生
    public void addStudent(Student student) {
        students.add(student);
    }

    // 删除学生
    public void deleteStudent(String id) {
        for (Student student : students) {
            if (student.getId().equals(id)) {
                students.remove(student);
                break;
            }
        }
    }

    // 修改学生信息
    public void modifyStudent(Student student) {
        for (int i = 0; i < students.size(); i++) {
            if (students.get(i).getId().equals(student.getId())) {
                students.set(i, student);
                break;
            }
        }
    }

    // 查询学生信息
    public Student queryStudent(String id) {
        for (Student student : students) {
            if (student.getId().equals(id)) {
                return student;
            }
        }
        return null;
    }

    // 获取所有学生信息
    public List<Student> getAllStudents() {
        return students;
    }
}

3. 在主函数中，实例化一个StudentManager对象，并进行测试。

public class Main {
    public static void main(String[] args) {
        StudentManager manager = new StudentManager();

        // 添加学生信息
        Student student1 = new Student("001", "张三", "男", 18, "一班", 90.0);
        Student student2 = new Student("002", "李四", "女", 19, "二班", 85.5);
        Student student3 = new Student("003", "王五", "男", 20, "三班", 92.0);
        manager.addStudent(student1);
        manager.addStudent(student2);
        manager.addStudent(student3);

        // 查询学生信息
        Student student = manager.queryStudent("001");
        if (student != null) {
            System.out.println("学号：" + student.getId() + "，姓名：" + student.getName() + "，班级：" + student.getClassName() + "，成绩：" + student.getScore());
        }

        // 修改学生信息
        student1.setScore(95.0);
        manager.modifyStudent(student1);

        // 删除学生信息
        manager.deleteStudent("003");

        // 获取所有学生信息
        List<Student> students = manager.getAllStudents();
        for (Student s : students) {
            System.out.println("学号：" + s.getId() + "，姓名：" + s.getName() + "，班级：" + s.getClassName() + "，成绩：" + s.getScore());
        }
    }
}

以上就是一个简单的Java学生管理系统的实现。