public class FruitItem {
int ID;
String name;
double price;
}
1 import java.util.ArrayList;
2 import java.util.Scanner;
3
4 public class Demo1 {
5
6 public static void mainMenu()// 菜单
7 {
8 System.out.println("==============欢迎光临超市==============");
9 System.out.println("1:货物清单" + " " + "2:添加新货物" + " " + "3:删除货物" + "4:修改货物" + "5:退出系统");
10 System.out.println("请输入要操作的功能序号");
11 }
12
13 public static void init(ArrayList<FruitItem> array)// 超市商品初始化
14 {
15 FruitItem fi1 = new FruitItem();
16 fi1.ID = 10;
17 fi1.name = "小鸡腿";
18 fi1.price = 3;
19 FruitItem fi2 = new FruitItem();
20 fi2.ID = 11;
21 fi2.name = "老干妈";
22 fi2.price = 13.5;
23 FruitItem fi3 = new FruitItem();
24 fi3.ID = 12;
25 fi3.name = "王老吉";
26 fi3.price = 4;
27 array.add(fi1);
28 array.add(fi2);
29 array.add(fi3);
30 }
31
32 public static void showFruitList(ArrayList<FruitItem> array)// 库存货物查询
33 {
34 System.out.println();
35 System.out.println("============商品清单============");
36 System.out.println("商品编号" + " " + "商品名称" + " " + "商品单价");
37 for (int i = 0; i < array.size(); i++) {
38 FruitItem fi = array.get(i);
39 System.out.println(fi.ID + " " + fi.name + " " + fi.price);
40 }
41
42 }
43
44 // 添加新货物
45 public static void addFruitItem(ArrayList<FruitItem> array) {
46 FruitItem fi = new FruitItem();
47 Scanner sc = new Scanner(System.in);
48 System.out.println("请输入新的商品编号");
49 fi.ID = sc.nextInt();
50 System.out.println("请输入新的商品名称");
51 fi.name = sc.next();
52 System.out.println("输入新商品的价格");
53 fi.price = sc.nextDouble();
54 boolean isNew = true;
55 for (int i = 0; i < array.size(); i++) {
56 FruitItem fi2 = array.get(i);
57 if (fi2.ID == fi.ID) {
58 isNew = false;
59 // array.remove(fi2);
60 // array.add(i, fi);
61 System.out.println("ID重复，请重新输入");
62 }
63 }
64 if (isNew) {
65 array.add(fi);
66 }
67 }
68
69 public static void delFruitItem(ArrayList<FruitItem> array)// 删除商品
70 {
71 System.out.println("选择的是删除商品功能");
72 System.out.println("请输入商品编号");
73 Scanner sc = new Scanner(System.in);
74 int ID = sc.nextInt();
75 for (int i = 0; i < array.size(); i++) {
76 FruitItem fi = array.get(i);
77 if (fi.ID == ID) {
78 array.remove(i);
79 System.out.println("删除成功");
80 return;// 当fi.ID == ID时，就删除了，没必要再循环比下去了，直接结束return
81 }
82 }
83 System.out.println("未找到该商品！");
84 }
85
86 public static void updateFruitItem(ArrayList<FruitItem> array) {
87 System.out.println("这是修改功能");
88 System.out.println("请输入需要修改的商品编号");
89 Scanner sc = new Scanner(System.in);
90 int ID = sc.nextInt();
91 System.out.println("您修改的商品编号为：" + ID);
92 for (int i = 0; i < array.size(); i++) {
93 if (array.get(i).ID == ID) {
94 System.out.println("请输入新的商品编号");
95 array.get(i).ID = sc.nextInt();
96 System.out.println("请输入新的商品名称");
97 array.get(i).name = sc.next();
98 System.out.append("请输入新的商品单价");
99 array.get(i).price = sc.nextDouble();
100 System.out.println("修改成功");
101 return;// 当编号相等，改商品数据成功后，没必要继续执行下面的输出语句
102 }
103 }
104 System.out.println("您输入的编号不存在");
105 }
106
107 public static void main(String[] args) {
108 ArrayList<FruitItem> array = new ArrayList<FruitItem>();
109 init(array);
110 Scanner sc = new Scanner(System.in);
111
112 while (true)// 死循环，一定要保证循环条件有变成false的时候
113 {
114 mainMenu();
115 int i = sc.nextInt();
116 switch (i) {
117 case 1:
118 showFruitList(array);// 货物清单
119 break;
120 case 2:
121 addFruitItem(array);// 添加新货物
122 break;
123 case 3:
124 delFruitItem(array);// 删除商品
125 break;
126 case 4:
127 updateFruitItem(array);// 修改商品
128 break;
129 case 5:
130 System.out.println("退出系统");
131 return;
132 default:
133 System.out.println("暂无此功能");
134 break;
135 }
136
137 }
138 }
139 }
