ArrayList集合的使用

import java.util.ArrayList;
class Demo02 
{
    public static void main(String[] args) 
    {
        method3();
    }
    public static void method1(){
        ArrayList<String> list = new ArrayList<String>();
        list.add("后裔");
        list.add("李元芳");
        list.add("猴子");
        System.out.println(list.get(0));
        System.out.println(list.size());
        for(int i = 0;i<list.size();i++){
             System.out.println(list.get(i));
        }
        
    }
    public static void method2(){
        ArrayList<phone> arr = new ArrayList<phone>();
        phone p1 = new phone();
        p1.brands = "oppo";
        p1.size = 5.5;
        p1.yanse = "red";
        arr.add(p1);
        phone p2 = new phone();
        p2.brands = "vivo";
        p2.size = 4.7;
        p2.yanse = "black";
        arr.add(p2);
        for(int i = 0;i<arr.size();i++){
               System.out.println(arr.get(i).brands+"	"+arr.get(i).size+"	"+arr.get(i).yanse);
        }
    }
    public static void method3(){
        ArrayList<Integer> arr = new ArrayList<Integer>();
        arr.add(100);
        arr.add(50);
        //指定位置插入数值
        arr.add(0,200);
        //删除指定位置数值
        arr.remove(1);
        //清空
        //arr.clear();
        //修改指定位置元素
        arr.set(0,30);
        for(int i = 0;i<arr.size();i++){
              System.out.println(arr.get(i));
        }
    }

}

public class Test01 
{
    public static void main(String[] args) 
    {
        Dianfanguo dfg = new Dianfanguo();
        Car c = new Car();
        Student s = new Student();
        dfg.brands = "格兰仕";
        dfg.size = 20;
        dfg.color = "红色";
        System.out.println("品牌:"+dfg.brands);
        System.out.println("尺寸:"+dfg.size);
        System.out.println("颜色:"+dfg.color+"
");
        c.brands = "科尼塞克";
        c.size = "4.0L";
        c.leixing = "跑车";
        System.out.println("品牌:"+c.brands);
        System.out.println("排量:"+c.size);
        System.out.println("类型:"+c.leixing+"
");
        s.name = "奥巴马";
        s.age = 50;
        s.sex = "男";
        System.out.println("姓名:"+s.name);
        System.out.println("年龄:"+s.age);
        System.out.println("性别:"+s.sex+"
");
    }
}

//ArrayList集合写随机点名
import java.util.ArrayList;
import java.util.Random;
import java.util.Scanner;
class zuoye 
{
    public static void main(String[] args) 
    {
        //cunchu();
        //bianli();
        //suiji();
        //cz();
        //sj();
        //yg();
    }
        public static void cunchu(){
         ArrayList<Stu> arr = new ArrayList<Stu>();
         Stu s0 = new Stu();
         s0.name = "董斌";
         s0.age = 20;
         Stu s1 = new Stu();
         s1.name = "张锐";
         s1.age = 21;
         Stu s2 = new Stu();
         s2.name = "王荣臣";
         s2.age = 22;
         Stu s3 = new Stu();
         s3.name = "韩凯";
         s3.age = 23;
         Stu s4 = new Stu();
         s4.name = "张禄";
         s4.age = 24;
         Stu s5 = new Stu();
         s5.name = "刘继勋";
         s5.age = 25;
         Stu s6 = new Stu();
         s6.name = "张维";
         s6.age = 26;
         Stu s7 = new Stu();
         s7.name = "牛攀";
         s7.age = 28;
         Stu s8 = new Stu();
         s8.name = "魏中豪";
         s8.age = 29;
         arr.add(s0);
         arr.add(s1);
         arr.add(s2);
         arr.add(s3);
         arr.add(s4);
         arr.add(s5);
         arr.add(s6);
         arr.add(s7);
         arr.add(s8);
    }
    public static void bianli(ArrayList<Stu> arr){
        ArrayList<Stu> arr = new ArrayList<Stu>();
         Stu s0 = new Stu();
         s0.name = "董斌";
         s0.age = 20;
         Stu s1 = new Stu();
         s1.name = "张锐";
         s1.age = 21;
         Stu s2 = new Stu();
         s2.name = "王荣臣";
         s2.age = 22;
         Stu s3 = new Stu();
         s3.name = "韩凯";
         s3.age = 23;
         Stu s4 = new Stu();
         s4.name = "张禄";
         s4.age = 24;
         Stu s5 = new Stu();
         s5.name = "刘继勋";
         s5.age = 25;
         Stu s6 = new Stu();
         s6.name = "张维";
         s6.age = 26;
         Stu s7 = new Stu();
         s7.name = "牛攀";
         s7.age = 28;
         Stu s8 = new Stu();
         s8.name = "魏中豪";
         s8.age = 29;
         arr.add(s0);
         arr.add(s1);
         arr.add(s2);
         arr.add(s3);
         arr.add(s4);
         arr.add(s5);
         arr.add(s6);
         arr.add(s7);
         arr.add(s8);
         System.out.println("姓名	年龄");
         for(int i = 0;i<arr.size();i++){
              System.out.println(arr.get(i).name+"	"+arr.get(i).age);
         }
    }
    public static void suiji(){
         Random r = new Random();
         int num = r.nextInt(9);
         ArrayList<Stu> arr = new ArrayList<Stu>();
         Stu s0 = new Stu();
         s0.name = "董斌";
         s0.age = 20;
         Stu s1 = new Stu();
         s1.name = "张锐";
         s1.age = 21;
         Stu s2 = new Stu();
         s2.name = "王荣臣";
         s2.age = 22;
         Stu s3 = new Stu();
         s3.name = "韩凯";
         s3.age = 23;
         Stu s4 = new Stu();
         s4.name = "张禄";
         s4.age = 24;
         Stu s5 = new Stu();
         s5.name = "刘继勋";
         s5.age = 25;
         Stu s6 = new Stu();
         s6.name = "张维";
         s6.age = 26;
         Stu s7 = new Stu();
         s7.name = "牛攀";
         s7.age = 28;
         Stu s8 = new Stu();
         s8.name = "魏中豪";
         s8.age = 29;
         arr.add(s0);
         arr.add(s1);
         arr.add(s2);
         arr.add(s3);
         arr.add(s4);
         arr.add(s5);
         arr.add(s6);
         arr.add(s7);
         arr.add(s8);
         System.out.println(arr.get(num).name+"	"+arr.get(num).age);
    }
//ArrayList集合编写库存系统
    public static void cz(){
        while(true){
             switch (xz())
             {
             case 1:show();
                     break;
             case 2:xg();
                     break;
             case 3:
                 return;
             default:
                 System.out.println("输入有误");
                     break;
             
             }
        }
    }
    public static int xz(){
        System.out.println("1、查看商品库存");
        System.out.println("2、修改库存数量");
        System.out.println("3、退出");
        System.out.println("输入操作编号");
        System.out.println("-----------------------------");
        Scanner sc = new Scanner(System.in);
        int num = sc.nextInt();
        return num;
    }
    public static void show(){
         ArrayList<Product> arr = new ArrayList<Product>();
         Product p0 = new Product();
         p0.name = "MackBookAir";
         p0.price = 6988.88;
         p0.size = 13.3;
         p0.count = 5;
         arr.add(p0);
         Product p1 = new Product();
         p1.name = "ThinkpadT450";
         p1.price = 5999.99;
         p1.size = 14.0;
         p1.count = 10;
         arr.add(p1);
         Product p2 = new Product();
         p2.name = "ASUS-FL5800";
         p2.price = 4999.5;
         p2.size = 15.6;
         p2.count = 18;
         arr.add(p2);
        System.out.println("----------------------商城库存清单--------------------");
        System.out.println("品牌型号	尺寸	价格	库存数");
        int csum = 0;
        for(int i=0;i<arr.size();i++){
          System.out.println(arr.get(i).name+"	"+arr.get(i).size+"	"+arr.get(i).price+"	"+arr.get(i).count);
          csum = csum + arr.get(i).count;
        }
        System.out.println("库存数	"+csum);
        System.out.println("---------------123------------------");
    }

    public static void xg(){
        ArrayList<Product> arr = new ArrayList<Product>();
         Product p0 = new Product();
         p0.name = "MackBookAir";
         p0.price = 6988.88;
         p0.size = 13.3;
         p0.count = 5;
         arr.add(p0);
         Product p1 = new Product();
         p1.name = "ThinkpadT450";
         p1.price = 5999.99;
         p1.size = 14.0;
         p1.count = 10;
         arr.add(p1);
         Product p2 = new Product();
         p2.name = "ASUS-FL5800";
         p2.price = 4999.5;
         p2.size = 15.6;
         p2.count = 18;
         arr.add(p2);
        System.out.println("商品编号"+"品牌型号	尺寸	价格	库存数");
        for(int i=0;i<arr.size();i++){
          System.out.println(i+"	"+arr.get(i).name+"	"+arr.get(i).size+"	"+arr.get(i).price+"	"+arr.get(i).count);
        }
        System.out.println("----------------------------------------------------");
        Scanner sc = new Scanner(System.in);
        System.out.println("输入编号");
        int num = sc.nextInt();
        System.out.println("输入数量");
        int n = sc.nextInt();
        arr.get(num).count = n;
    }
    public static void sj(){
         ArrayList<Pho> arr = new ArrayList<Pho>();
         Pho p0 = new Pho();
         p0.brand = "小米";
         p0.price = 1999.0;
         p0.color = "blue";
         arr.add(p0);
         Pho p1 = new Pho();
         p1.brand = "华为";
         p1.price = 3999.0;
         p1.color = "white";
         arr.add(p1);
         Pho p2 = new Pho();
         p2.brand = "乐视";
         p2.price = 999.0;
         p2.color = "black";
         arr.add(p2);
         Pho p3 = new Pho();
         p3.brand = "奇酷";
         p3.price = 2999;
         p3.color = "red";
         arr.add(p3);
         for(int i = 0;i<arr.size();i++){
              System.out.println(arr.get(i).brand+"	"+arr.get(i).price+"	"+arr.get(i).color);
         }
    }


    public static void yg(){
         ArrayList<Employee> arr = new ArrayList<Employee>();
         Employee e0 = new Employee();
         e0.name = "张三";
         e0.num = 10;
         e0.salary = 3000;
         arr.add(e0);
         Employee e1 = new Employee();
         e1.name = "李四";
         e1.num = 20;
         e1.salary = 4000;
         arr.add(e1);
         Employee e2 = new Employee();
         e2.name = "王五";
         e2.num = 30;
         e2.salary = 5000;
         arr.add(e2);
         for(int i = 0;i<arr.size();i++){
              System.out.println(arr.get(i).name+"	"+arr.get(i).num+"	"+arr.get(i).salary);
         }
    }
         //简述自定义数据类型的定义格式和使用方式？
         //创建java文件，与类名相同
         //public class 类名{
         //数据类型  属性名称1；
        // 数据类型  属性名称2；
        // …
        // }
         //导包：我们将所有的类放到同一个文件夹下，可以避免导包。
         // 创建对象：数据类型  变量名 = new 数据类型();
         //调用方法：目前我们定义的自定义类不涉及方法，只是属性（自定义类中的方法部分在面向对象部分讲解）
         // 访问属性：变量名.属性
          //简述ArrayList集合的定义格式和常用方法的功能？
         //导包：import java.util.ArrayList;
        // 创建对象：与其他普通的引用数据类型创建方式完全相同，但是要指定容器中存储的数据类型：
        // ArrayList<要存储元素的数据类型> 变量名 = new ArrayList<要存储元素的数据类型>();
         //arr.add();
        // arr.get();
        // arr.size();
        // arr.set();
        // arr.remove();
        // arr.clear();


    }