Java ArrayList 某中学有若干学生，每个学生有一个姓名属性、班级名称属性和考试成绩属性

题目：某中学有若干学生(学生对象放在一个List中)，每个学生有一个姓名属性、班级名称属性(String)和考试成绩 属性(int)，某次考试结束后，每个学生都获得了一个 考试成绩。请打印出每个班级的总分和平均分。

学生类：为了方便这里只提供了get方法。

public class Student {
   
	private String name;
	private String className;
	private int grade;

	public String getName() {
   
		return name;
	}
	public String getClassName() {
   
		return className;
	}
	public int getGrade() {
   
		return grade;
	}
	
	public Student(String name, String className, int grade) {
   
		this.name = name;
		this.className = className;
		this.grade = grade;
	}
}

测试类

public class TestStudent {
   
	public static void main(String[] args) {
   
		// 给每个对象设置属性
		Student student1 = new Student("曹操", "魏国", 100);
		Student student2 = new Student("司马懿", "魏国", 98);
		Student student3 = new Student("张飞", "蜀国", 89);
		Student student4 = new Student("关羽", "蜀国", 89);
		Student student5 = new Student("赵云", "蜀国", 97);
		Student student6 = new Student("刘备", "蜀国", 96);
		Student student7 = new Student("荀彧", "魏国", 99);
		Student student8 = new Student("张郃", "魏国", 88);

		// 将对象放入list
		List<Object> list = new ArrayList<Object>();
		list.add(student1);
		list.add(student2);
		list.add(student3);
		list.add(student4);
		list.add(student5);
		list.add(student6);
		list.add(student7);
		list.add(student8);

		Student stu;
		// 定义两个存分数的数组
		List<Integer> wei = new ArrayList<Integer>();
		List<Integer> shu = new ArrayList<Integer>();

		// 将每个班的分数放到一个数组
		for (int i = 0; i < list.size(); i++) {
   
			stu = (Student) list.get(i);
			if (stu.getClassName().equals("魏国")) {
   
				wei.add(stu.getGrade());
			} else {
   
				shu.add(stu.getGrade());
			}
		}

		// 总分
		double shuSum = 0;
		double weiSum = 0;

		for (int i = 0; i < shu.size(); i++) {
   
			shuSum += shu.get(i);
			weiSum += wei.get(i);
		}
		System.out.println("魏国分数：" + wei);
		System.out.println("魏国的总分：" + weiSum + " 魏国的平均分：" + weiSum / wei.size());
		System.out.println("蜀国分数：" + shu);
		System.out.println("蜀国的总分：" + shuSum + " 蜀国的平均分：" + shuSum / shu.size());
	}
}