Java学生管理系统

只是为了练习接口设计的一个学生系统小案例,算不上真正的学生管理系统.

需求说明

概要设计

image-20240117173051203

具体实现

image-20240117174122286

CodeDemo

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// showAll 接口
public interface ShowAll {
    void printInfo();
}

// showAvg 接口
public interface ShowAvg {
    void showAvg();
}

// A类
import java.util.ArrayList;

public class A implements ShowAll, ShowAvg{
    private ArrayList<Student> list = new ArrayList<>();
    public A(){
        Student s1 = new Student("张三", '男', 99);
        Student s2 = new Student("李四", '女', 88);
        Student s3 = new Student("王五", '男', 95);
        list.add(s1);
        list.add(s2);
        list.add(s3);
    }
    @Override
    public void printInfo() {
        for (int i = 0; i < list.size(); i++) {
            Student student = list.get(i);
            System.out.println("学生姓名:" +student.getName()+"\t学生性别:"+student.getSex()+"\t学生成绩:" + student.getScore());
        }
    }

    @Override
    public void showAvg() {
        double sum = 0;
        int count = 0;
        for (int i = 0; i < list.size(); i++) {
            Student student = list.get(i);
            sum += student.getScore();
            count ++;
        }
        System.out.println("平均成绩为:" + sum/count);

    }
}

//B类
import java.util.ArrayList;

public class B implements ShowAvg, ShowAll{
    private ArrayList<Student> list = new ArrayList<>();
    public B(){
        Student s1 = new Student("张三", '男', 99);
        Student s2 = new Student("李四", '女', 88);
        Student s3 = new Student("王五", '男', 95);
        list.add(s1);
        list.add(s2);
        list.add(s3);
    }
    @Override
    public void printInfo() {
        int maleNum = 0;
        int femalNum = 0;
        for (int i = 0; i < list.size(); i++) {
            Student student = list.get(i);
            if (student.getSex() == '男'){
                maleNum ++;
            }else if (student.getSex() == '女'){
                femalNum ++;
            }
            System.out.println("学生姓名:" +student.getName()+"\t学生性别:"+student.getSex()+"\t学生成绩:" + student.getScore());
        }
        System.out.println("班级中男生人数为:"+maleNum + "\t女生人数为:" + femalNum);
    }

    @Override
    public void showAvg() {
        Student student = list.get(0);
        double minScore = student.getScore();
        double maxScore = student.getScore();
        double sum = student.getScore();
        int count = 1;
        for (int i = 1; i < list.size(); i++) {
            Student student1 = list.get(i);
            if (student1.getScore() < minScore){
                minScore = student1.getScore();
            }else if (student1.getScore() > maxScore){
                maxScore = student1.getScore();
            }
            sum += student1.getScore();
            count ++;
        }
        System.out.println("去掉最高分,去掉最低分,全班学生的平均成绩为:" + (sum - minScore - maxScore)/ (count-2));
    }
}


// Student类是标准的JavaBean
public class Student {
    private String name;
    private char sex;
    private double score;

    @Override
    public String toString() {
        return "Student{" +
                "name='" + name + '\'' +
                ", sex=" + sex +
                ", score=" + score +
                '}';
    }

    public String getName() {
        return name;
    }

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

    public char getSex() {
        return sex;
    }

    public void setSex(char sex) {
        this.sex = sex;
    }

    public double getScore() {
        return score;
    }

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

    public Student(String name, char sex, double score) {
        this.name = name;
        this.sex = sex;
        this.score = score;
    }

    public Student() {
    }
}


// Test类
public class Test {
    public static void main(String[] args) {
        B a = new B();
        a.printInfo();
        a.showAvg();
    }
}