【Java】基础知识整合——学生管理系统（ArrayList实现）

public class Studentinfo {
    //成员：姓名，年龄，学号，专业
    private String name;
    private String age;
    private String id;
    private String major;

    //空构造器
    public Studentinfo()
    {

    }
    //构造器
    public Studentinfo(String name,String age,String id,String major)
    {
        this.name = name;
        this.age  = age;
        this.id   = id;
        this.major= major;
    }

    //方法：get与set
    public void setName (String name)    {  this.name = name; }
    public void setAge  (String age)     {  this.age  = age;  }    
    public void setId   (String id)      {  this.id   = id;   }
    public void setMajor(String major)   {  this.major= major;}

    public String getName()  { return this.name; }
    public String getAge()   { return this.age;  }
    public String getId()    { return this.id;   }
    public String getMajor() { return this.major;}

}

import java.util.Scanner;
import java.util.ArrayList;

public class Student_Managment_System {
    public static void main(String[] args)
    {
        //初始界面：
        System.out.println("---------------------------");
        System.out.println("    ***学生管理系统***");
        System.out.println("    你可以进行如下操作:");
        System.out.println("   1.添加学生及其信息");
        System.out.println("   2.删除学生及其信息");
        System.out.println("   3.浏览所有系统内学生信息");
        System.out.println("   4.修改学生信息");
        System.out.println("   5.退出");
        System.out.println("---------------------------");
        System.out.print("你想进行的操作序号是:");

       //总集合，存放所有Studentinfo类的实例
       ArrayList student_Array= new ArrayList();

        int x=1;
        while(x == 1)   //一直循环
        {
            //输入操作序号：
            Scanner ope_num = new Scanner(System.in);
            int Operation_Number = ope_num.nextInt(); 

            int flag=0;  //标志变量
            //进行对应操作：
            switch(Operation_Number)
            {
                case 1:     //添加
                {
                    addStudent(student_Array);
                    flag=0;
                    break;
                }
                case 2:
                {
                    deletStudent(student_Array);
                    flag=0;
                    break;
                }
                case 3:
                {
                    showAllStudents(student_Array);
                    flag=0;
                    break;
                }
                case 4:
                {
                    modifyStudentinfo(student_Array);
                    flag=0;
                    break;
                }
                case 5:
                {
                    System.out.println("谢谢使用!您已退出系统。");
                    flag=1;
                    break;
                }
                default:
                {
                    System.out.println("请重新输入正确的操作序号!");
                    flag=0;
                    break;
                }
            }
            
            if(flag==1)    
            {
                break;
            }
            else 
            {
                System.out.println();
                System.out.print("你想进行的操作序号是:");
            }

        }//END of while(1)
    
    }
 
    //case 1 调用:添加学生
    public static void addStudent(ArrayList student_Array)   
    {
        Scanner p = new Scanner(System.in);    //通过p输入赋值
        Studentinfo stu = new Studentinfo();     //stu是Student类的实例对象

        System.out.print("该学生的名字是:");
        String name = p.nextLine();   //stu.setName(p.nextLine());也是可以的
        stu.setName(name);
        System.out.print("该学生的年龄是:");
        String age = p.nextLine();
        stu.setAge(age);
        //这里遇到过bug：如果将age定义成int类，输入后回车将会将回车读入id中，所以只能将age定义成String类
        System.out.print("该学生的学号是:");   
        String id = p.nextLine();
        stu.setId(id);
        System.out.print("该学生的专业是:");
        String major = p.nextLine();
        stu.setMajor(major);

        //Studentinfo类的对象stu的所有成员都被赋予了值，现在转存入student_Array
        student_Array.add(stu);

        System.out.println("提交成功!");
    }

    //case 2调用:删除学生
    public static void deletStudent(ArrayList student_Array)
    {
        Scanner p = new Scanner(System.in);
        Studentinfo stu = new Studentinfo();

        System.out.print("你要删除的学生的名字是:");
        String name = p.nextLine();
        for(int i=0; i student_Array)
    {
        System.out.println("姓名t年龄t学号tt专业");   // t=Tab
        for(int i=0; i student_Array)
    {
        Scanner p = new Scanner(System.in);
        Studentinfo stu = new Studentinfo();

        System.out.print("你想修改的学生的名字是:");
        for(int i=0; i