安安的code日記

今天練習了一個題目-學生資訊系統

功能：

輸入1-6來決定功能

1.新增學生資料 2.輸入座位印出成績 3.成績高至低列印 4.座位低至高印出 5.輸入座位更改成績 6.結束程式

要思考更多，像是功能要放在哪一個類別之類的

以下main程式

import java.util.Scanner;

public class MainClass {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        Student std[] = new Student[2];
        int count = 0;
        boolean toggle = true; //功能選單開關
        while (toggle) {
            System.out.print("請選擇服務項目:\n1.新增學生資料\t2.印出個人成績\t3.依照成績高至低排列印出\n" +
                    "4.依照座位低至高排列印出\t5.更改成績\t6.結束程式\n");
            int select = sc.nextInt();
            switch (select) {
                case 1:
                    if (count == std.length) {      //陣列加長控制
                        std = doubleArray(std);
                    }
                    std[count++] = newStudent();      //將物件放入Student陣列中
                    break;
                case 2:
                    System.out.println("請輸入要列印之座號：");
                    int seat = sc.nextInt();
                    for (int i = 0; i < count; i++) {   //尋找陣列中有無跟輸入值一樣的座位號碼
                        if (std[i].getSeat() == seat)
                            std[i].printScore();    //有的話印出來
                        break;
                    }
                    System.out.println("查無此座號");
                    break;
                case 3:
                    bigToSmall(std, count);    //排列大到小
                    for (int i = 0; i < count; i++) {
                        std[i].printAll();
                    }
                    break;
                case 4:
                    smallToBigSeat(std, count);     //排列小到大
                    for (int i = 0; i < count; i++) {
                        std[i].printAll();
                    }
                    break;
                case 5:
                    System.out.print("請輸入更改成績之座號：");
                    seat = sc.nextInt();
                    for (int i = 0; i < count; i++) {   //尋找陣列中有無跟輸入值一樣的座位號碼
                        if (std[i].getSeat() == seat) {
                            System.out.print("請輸入新成績：");
                            int newScore = sc.nextInt();
                            std[i].changeScore(newScore);
                            break;
                        }
                    }
                    System.out.println("查無此座號");
                    break;
                case 6:
                    toggle = false;
                    break;
            }
        }
        System.out.print("程式已關閉");

    }

    public static Student[] doubleArray(Student std[]) {
        Student newStd[] = new Student[(std.length * 2)];
        System.arraycopy(std, 0, newStd, 0, std.length);
        return newStd;
    }

    public static Student newStudent() {    //建立Student物件
        Scanner sc = new Scanner(System.in);
        System.out.print("請輸入班級：");
        String classNum = sc.nextLine();
        System.out.print("請輸入姓名：");
        String name = sc.nextLine();
        System.out.print("請輸入座號：");
        int seat = sc.nextInt();
        System.out.print("請輸入分數：");
        int score = sc.nextInt();
        Student std = new Student(classNum, name, seat, score);
        return std;
    }

    public static void swap(Student[] std, int a, int b) {
        Student tmp[] = new Student[1];
        tmp[0] = std[a];
        std[a] = std[b];
        std[b] = tmp[0];
    }


    public static void bigToSmall(Student std[], int count) {
        for (int i = 0; i < count; i++) {
            for (int j = 1; j < count - i; j++) {
                if (std[i].getScore() < std[i + j].getScore()) {    //判斷物件的成績大小
                    swap(std, i, (i + j));
                }
            }
        }
    }

    public static void smallToBigSeat(Student std[], int count) {
        for (int i = 0; i < count; i++) {
            for (int j = 1; j < count - i; j++) {
                if (std[i].getSeat() > std[i + j].getSeat()) {
                    swap(std, i, (i + j));
                }
            }
        }
    }

    public static void smallToBig(Student std[], int count) {
        for (int i = 0; i < count; i++) {
            for (int j = 1; j < count - i; j++) {
                if (std[i].getScore() > std[i + j].getScore()) {
                    swap(std, i, (i + j));
                }
            }
        }
    }


}

 Student 類別

import java.util.Scanner;

public class Student {
    private int score;
    private String classNum;
    private String name;
    private int seat;
    //建構子
    public Student(String classNum, String name, int seat, int score) {
        setClassNum(classNum);
        setName(name);
        setSeat(seat);
        setScore(score);
    }
    public Student(String classNum, String name, int seat) {
        this(classNum,name,seat,0);
    }

    public void printScore() {
        System.out.println(this.score + "分");

    }

    public void printAll(){
        System.out.print("班級：" + this.getClassNum() + "\t座號：" + this.getSeat() +
                "\t姓名：" + this.getName() + "\t" + this.getScore() + "分\n" );
    }

    public void changeScore(int newScore){
        setScore(newScore);
    }




    public int getScore() {
        return score;
    }

    private void setScore(int score) {
        if (score > 100) {
            this.score = 100;
        }else if (score < 0) {
            this.score = 0;
        } else {
            this.score = score;
        }
    }

    public String getClassNum() {
        return classNum;
    }

    private void setClassNum(String classNum) {
        this.classNum = classNum;
    }

    public String getName() {
        return name;
    }

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

    public int getSeat() {
        return seat;
    }

    private void setSeat(int seat) {
        this.seat = seat;
    }
}