Java-Project01 家庭收支记账软件

 1 class exces{
 2 
 3     public static void main(String[] args){
 4     
 5     boolean isFlag = true;    
 6     
 7     String details = "";
 8     int  money = 10000;
 9     
10 
11     while(isFlag){
12         System.out.print("------------------家庭收支记账软件-----------------\n");
13         System.out.print("                 1.收支明细\n");
14         System.out.print("                 2.登记收入\n");
15         System.out.print("                 3.登记支出\n");
16         System.out.print("                 4.退    出\n");
17         System.out.print("                请选择（1-4）");
18     int choice = Utility.readMenuSelection();
19     switch(choice){
20     case '1':
21         System.out.println("--------------------当前收入明细--------------------");
22         System.out.print("收支" + "\t" + "账户金额" + "\t" + "收支金额" + "\t" + "说    明"+ "\n");
23         System.out.print(details);
24         System.out.println("----------------------------------------------------");
25         break;    
26     case '2':
27         System.out.print("本次收入金额：");
28         int addMoney = Utility.readNumber();
29         if(addMoney <= 0){
30             System.out.println("输入错误,请重新选择");
31             break;}
32         System.out.print("本次收入说明：");
33         String addInfo = Utility.readString();    
34         money = money + addMoney;
35         details += "收入\t" + money + "\t" + "\t" + addMoney + "\t" + "\t" + addInfo + "\n";
36         break;    
37     case '3':
38         System.out.print("本次支出金额：");
39         int lowMoney = Utility.readNumber();
40         if(lowMoney <= 0){
41             System.out.println("输入错误,请重新选择");
42             break;}
43         System.out.print("本次支出说明：");
44         String lowInfo = Utility.readString();    
45         money = money - lowMoney;
46         if(money <= 0){
47             System.out.println("输入金额溢出，请重新输入");}
48         details += "支出\t" + money + "\t" + "\t" + lowMoney + "\t" + "\t" + lowInfo + "\n";
49         break;    
50     case '4':
51         System.out.print("确定是否退出(Y/N):");
52         char select = Utility.readConfirmSelection();
53         if(select == 'Y'){
54             System.out.println("祝您生活愉快！");
55             isFlag = false;
56         }else if(select == 'N'){
57             break;
58         }
59 }
60 
61 }
62 }
63 }

import java.util.Scanner;
/**
Utility工具类：
将不同的功能封装为方法，就是可以直接通过调用方法使用它的功能，而无需考虑具体的功能实现细节。
*/
public class Utility {
    private static Scanner scanner = new Scanner(System.in);
    /**
    用于界面菜单的选择。该方法读取键盘，如果用户键入’1’-’4’中的任意字符，则方法返回。返回值为用户键入字符。
    */
    public static char readMenuSelection() {
        char c;
        for (; ; ) {
            String str = readKeyBoard(1);
            c = str.charAt(0);
            if (c != '1' && c != '2' && c != '3' && c != '4') {
                System.out.print("选择错误，请重新输入：");
            } else break;
        }
        return c;
    }
    /**
    用于收入和支出金额的输入。该方法从键盘读取一个不超过4位长度的整数，并将其作为方法的返回值。
    */
    public static int readNumber() {
        int n;
        for (; ; ) {
            String str = readKeyBoard(4);
            try {
                n = Integer.parseInt(str);
                break;
            } catch (NumberFormatException e) {
                System.out.print("数字输入错误，请重新输入：");
            }
        }
        return n;
    }
    /**
    用于收入和支出说明的输入。该方法从键盘读取一个不超过8位长度的字符串，并将其作为方法的返回值。
    */
    public static String readString() {
        String str = readKeyBoard(8);
        return str;
    }
    
    /**
    用于确认选择的输入。该方法从键盘读取‘Y’或’N’，并将其作为方法的返回值。
    */
    public static char readConfirmSelection() {
        char c;
        for (; ; ) {
            String str = readKeyBoard(1).toUpperCase();
            c = str.charAt(0);
            if (c == 'Y' || c == 'N') {
                break;
            } else {
                System.out.print("选择错误，请重新输入：");
            }
        }
        return c;
    }
    
    
    private static String readKeyBoard(int limit) {
        String line = "";

        while (scanner.hasNext()) {
            line = scanner.nextLine();
            if (line.length() < 1 || line.length() > limit) {
                System.out.print("输入长度（不大于" + limit + "）错误，请重新输入：");
                continue;
            }
            break;
        }

        return line;
    }
}

参考代码:

 1 public class FamilyAccount {
 2     public static void main(String[] args) {
 3         String details = "收支\t账户金额\t收支金额\t说    明\n";
 4         int balance = 10000;
 5 
 6         boolean loopFlag = true;
 7         do {
 8             System.out.println("\n-----------------家庭收支记账软件-----------------\n");
 9             System.out.println("                   1 收支明细");
10             System.out.println("                   2 登记收入");
11             System.out.println("                   3 登记支出");
12             System.out.println("                   4 退    出\n");
13             System.out.print("                   请选择(1-4)：");
14             
15             char key = Utility.readMenuSelection();
16             System.out.println();
17             switch (key) {
18                 case '1':
19                     System.out.println("-----------------当前收支明细记录-----------------");
20                     System.out.println(details);
21                     System.out.println("--------------------------------------------------");
22                     break;
23                 case '2':
24                     System.out.print("本次收入金额：");
25                     int amount1 = Utility.readNumber();
26                     System.out.print("本次收入说明：");
27                     String desc1 = Utility.readString();
28 
29                     balance += amount1;
30                     details += "收入\t" + balance + "\t\t" +
31                                amount1 + "\t\t" + desc1 + "\n";
32                     System.out.println("---------------------登记完成---------------------");
33                     break;
34                 case '3':
35                     System.out.print("本次支出金额：");
36                     int amount2 = Utility.readNumber();
37                     System.out.print("本次支出说明：");
38                     String desc2 = Utility.readString();
39 
40                     balance -= amount2;
41                     details += "支出\t" + balance + "\t\t" +
42                                amount2 + "\t\t" + desc2 + "\n";
43                     System.out.println("---------------------登记完成---------------------");
44                     break;
45                 case '4':
46                     System.out.print("确认是否退出(Y/N)：");
47                     char yn = Utility.readConfirmSelection();
48                     if (yn == 'Y') loopFlag = false;
49                     break;
50             }
51         } while (loopFlag);
52     }    
53 }