Java 学生类

题目

• “对一共有10名学生的班级进行一次测试。已知每个学生这次测试的成绩，求这次测验的班级平均成绩、最高成绩、最低成绩，并统计本次考试成绩的分布情况。”

• 用面向对象的思路写成类的形式，设计学生类和班级类，使用对象的组合，班级类中的成员为学生类的对象学生。

题解

源代码如下：

class Student { //学生类
    String name;
    double score;

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

class Class { //班级类
    Student[] s;

    Class(Student[] s) {
        this.s = s;
    }

    double getAverage() { //平均成绩
        double sum = 0;
        for (int i = 0; i < s.length; i++) {
            sum += s[i].score;
        }
        return sum / s.length;
    }

    double getMax() { //最高成绩
        double maxScore = 0;
        for (int i = 0; i < s.length; i++) {
            if (s[i].score > maxScore) {
                maxScore = s[i].score;
            }
        }
        return maxScore;
    }

    double getMin() { //最低成绩
        double minScore = 100;
        for (int i = 0; i < s.length; i++) {
            if (s[i].score < minScore) {
                minScore = s[i].score;
            }
        }
        return minScore;
    }

    String gradeDistribution() { //本次考试成绩的分布情况
        int great = 0;
        int good = 0;
        int pass = 0;
        int failure = 0;
        for (int i = 0; i < s.length; i++) {
            int grade = (int) (s[i].score / 10);
            switch (grade) {
                case 10:
                case 9:
                    great++;
                    break;
                case 8:
                case 7:
                    good++;
                    break;
                case 6:
                    pass++;
                    break;
                default:
                    failure++;
                    break;
            }
        }
        return "优秀：" + great + " 良好：" + good + " 及格：" + pass + " 不及格：" + failure;
    }
}

public class Test2 {
    public static void main(String[] args) {

        String[] name = {"weimeng", "zhao", "qian", "sun", "li", "zhou", "wu", "zheng", "wang", "zhang"};
        double[] score = {100, 70, 81, 90, 60, 50, 78, 45, 58, 80};
        Student[] stu = new Student[10];
        for (int i = 0; i < stu.length; i++) {
            stu[i] = new Student(name[i], score[i]);
        }
        Class c = new Class(stu);
        System.out.println("平均分：" + c.getAverage());
        System.out.println("最高分：" + c.getMax());
        System.out.println("最低分：" + c.getMin());
        System.out.println("成绩分布：" + c.gradeDistribution());
    }
}

运行结果：

平均分：71.2
最高分：100.0
最低分：45.0
成绩分布：优秀：2 良好：4 及格：1 不及格：3