简单的学生管理系统

给一个学生数组,要求实现增删改查.
按照面向对象的思路来看
需求分析:
1要有一个学生类(用来存储学生的信息)
2要有一个管理类(实现各种方法,即讲个中方法封装放到里面)
3要有一个测试类(就是调用管理类的类)
如果你是新手,你可以理解为,我们要管理一些学生.分为:
1.要有一群学生
2.管理学生的方法

ScreenClip [1].png

首先先创建一个学生类

package StudentManager;
public class Student {
    static int num = 0;
    String name;
    int xh;
    boolean sex;
    public Student() {
        this.xh = num++;
    }
    public String toString() {
        String temp = "男";
        if (!sex) {
            temp = "女";
    }
        String str = "学号=" + this.xh + "姓名=" + this.name + "性别=" + temp;
        return str;
    }
}

创建管理类

package StudentManager;
public class Control {  
    int index= 0;
    //
    Student[] stu = new Student[3];
    //初始化
    void init(){
        Student student = new Student();
        student.name = "张三";
        student.sex = true;
        Student student1 = new Student();
        student1.name = "王五";
        student.sex = false;
        stu[0]=student;
        stu[1]=student1;
        this.index = 2;
        System.out.println("=====学生信息展示=======");
    }
    //重写构造方法
    public Control(){
        this.init();
    }
    //查看
    void show(){
        System.out.println("--------------------");
        //遍历存储学生
        for (int i = 0; i < this.index; i++) {
            //打印学生的信息
            System.out.println(stu[i]);
        }
    }
    //根据id查找学生
    Student selectStudent(int xh){
        for (int i = 0; i < index; i++) {
            if (this.stu[i].xh == xh) {
                System.out.println(this.stu[i]);
                return this.stu[i];
            }
        }
        return null;
    }
    //根据id删除学生
    Student deleteByXh(int xh){
        if (xh < 0) {
            return null;
        }
        //先找学生
        int tag=-1;
        for (int i = 0; i < index; i++) {
            if (xh==this.stu[i].xh) {
                tag = i;
                break;
            }
        }
        if (tag== -1) {//证明没找到学生
            return null;
        }
        //记录要删除的元素
        Student temp = this.stu[tag];
        for (int i = tag; i < index-1; i++) {
            this.stu[i] = this.stu[i+1];
        }
        index--;
        return temp;
    }
    //4增加学生
    void addStudent(Student stu){
        if (index <this.stu.length) {
        this.stu[index] = stu;
        index ++;
        }else {
            //扩展数组
            this.expand();
            //添加
            this.addStudent(stu);
            }
    }
    //扩展
    void expand(){
        Student[] stus = new Student[this.stu.length + 2];
        for (int i = 0; i < index; i++) {
            stus[i] = this.stu[i];      
        }
        this.stu = stus;//把新数组赋值给数组
    }
    //5 修改学生信息 stu
    //要修改学生的id
    void upDateStudentByStudent(Student stu){
        Student student = this.selectStudent(stu.xh);
        //修改
        student.name = stu.name;
        student.sex = stu.sex;
    }
}

测试类

package StudentManager;
public class test {
    public static void main(String[] args) {
        Control control = new Control();
        control.selectStudent(0);
        control.show();
        control.deleteByXh(1);
        control.show();
        Student stu1 = new Student();
        stu1.name = "老王";
        stu1.sex = true;
        control.addStudent(stu1);
        control.show();
        stu1.name = "老张";
        control.upDateStudentByStudent(stu1);
    }
}

效果展示

ScreenClip [2].png