學生資訊查詢

功能：

1.通過id修改學生資訊

2.獲取指定學生的成績

3.獲取指定學號的成績

4.根據姓名修改指定學科的成績

5.刪除指定學生及其成績

6.統計所有成績相等的人數

7.獲取到所有學生某一科的成績

程式碼塊

package com.lanou.work01;

import java.util.ArrayList;
import java.util.HashSet;

public class ProgramSystem {

    public static void main(String[] args) {
        ArrayList<Student> listStudent = new
 
 ArrayList<Student>();

        // 學生小李
        Student student = new Student(1, "小李");
        Subject subject1 = new Subject("語文", 90.7);
        Subject subject2 = new Subject("數學", 10.5);
        student.list.add(subject1);
        student.list.add(subject2);

        // 學生小王
        Student student2 = new
 
 Student(1, "小王");
        Subject subject3 = new Subject("語文", 20.7);
        Subject subject4 = new Subject("數學", 10.5);
        student2.list.add(subject3);
        student2.list.add(subject4);

        // 裝進大的陣列
        listStudent.add(student);
        listStudent.add(student2);
        System.out.println(listStudent.size());

        Control control = new
 
 Control(listStudent);
        //以下注釋內容為功能測試
        // control.getScore(student, "語文");
        // System.out.println("-------------------------");
        // control.getId(1, "數學");
        // System.out.println("-------------------------");
        // control.upDateName(1, "小陳");
        // System.out.println(student.nameString);
        // System.out.println("-------------------------");
        // control.upDateScore("小陳", "語文", 0.0);
        // System.out.println(student);
        // control.removeStudent(student);
        // System.out.println(listStudent);
        // control.countStudnet(student, "語文");
        control.fun("語文");
    }
}

class Control {
    // 存放學生的陣列
    ArrayList<Student> listStudent = new ArrayList<Student>();

    public Control(ArrayList<Student> listStudent) {
        this.listStudent = listStudent;
    }
    //展示方法
    public void show(){
        System.out.println("*************************");
    }

    // 獲取指定學生的成績
    public void getScore(Student student, String bookName) {
        for (Student student2 : listStudent) {
            if (student.nameString.equals(student2.nameString)) {

                for (Subject sub : student.list) {
                    // 每一個成績類物件
                    if (bookName.equals(sub.nameBook)) {
                        System.out.println(sub.Score);
                    }
                }
            }

        }
    }
    // 獲取指定學號的成績
    public void getId(int id, String bookName) {
        for (Student student2 : listStudent) {
            if (student2.id == id) {// 如果id相等話
                for (Subject sub : student2.list) {
                    // 每一個成績類物件
                    if (bookName.equals(sub.nameBook)) {
                        System.out.println(sub.Score);
                    }
                }

            }

        }
    }

    // 根據id修改姓名
    public void upDateName(int id, String name) {
        for (Student student : listStudent) {
            if (student.id == id) {// 如果想等的話
                student.nameString = name;
            }
        }
    }

    // 根據姓名修改指定學科的成績
    public void upDateScore(String name, String bookName, Double score) {
        for (Student student : listStudent) {
            if (student.nameString.equals(name)) {
                for (Subject subject : student.list) {
                    if (subject.nameBook.equals(bookName)) {
                        subject.Score = score;
                    }
                }
            }
        }
    }
    // 刪除指定學生及其成績
    public void removeStudent(Student student) {
        Student student3 = new Student();
        System.out.println(listStudent);
        for (Student student2 : listStudent) {
            if (student2.nameString.equals(student.nameString)) {
                student3 = student2;
            }
        }
        listStudent.remove(student3);
    }

    // 統計所有成績相等的人數
    public void countStudnet(Student student, String namString) {
        int count = 1;
        // 建立一個數組
        double array[] = new double[listStudent.size()];
        System.out.println(listStudent.size());
        for (Student student2 : listStudent) {
            for (int i = 0; i < array.length; i++) {
                System.out.println("陣列的長度"+array.length);
                for (Subject subject : student2.list) {
                    if (subject.nameBook.equals(namString)) {
                        System.out.println(namString);
                        array[i] = subject.Score;
                        System.out.println(array[i]);
                    }
                }
            }
        }
        // 第一個和第二個比較
        for (int i = 0; i < array.length; i++) {
            for (int j = i + 1; j < array.length; j++) {
                if (array[i] == array[j]) {
                    count++;
                }
            }
        }
        System.out.println("語文成績相等的人數為：" + count);

    }

    // 獲取到所有學生的成績
    public void fun(String nameString) {
        HashSet<Double> set = new HashSet<Double>();
        for (Student student2 : listStudent) {
                    for (Subject subject : student2.list) {
                         if (nameString.equals(subject.nameBook)) {
                            set.add(subject.Score); 
                        }   
                    }   
            }
        System.out.println(set);
    }
}
//學生類
class Student {

    String nameString;
    int id;
    ArrayList<Subject> list = new ArrayList<Subject>();

    public Student(int id, String nameString) {
        this.id = id;
        this.nameString = nameString;

    }

    @Override
    public String toString() {
        // TODO Auto-generated method stub
        for (Subject subject : list) {
            return "姓名:" + nameString + "學號:" + id + "成績單:" + subject.nameBook
                    + subject.Score;
        }
        return null;

    }

    public Student() {

    }
}

// 學科類
class Subject {

    String nameBook;
    double Score;

    public Subject(String nameBook, double score) {
        super();
        this.nameBook = nameBook;
        Score = score;
    }

}