家庭收支记录程序

Utility.java

工具类，不用自己写。

import java.util.Scanner;
/**
Utility工具类

*/
public class Utility {
    private static Scanner scanner = new Scanner(System.in);
    /**
	如果用户输入1-4的任意字符按方法返回
	*/
	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。
	*/
    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;
    }
	/**
	用于收入和支出的说明情况。
	*/
    public static String readString() {
        String str = readKeyBoard(8);
        return str;
    }

	/**
    用于确认选择的输入，读取输入Y或者N
	*/
    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("输入错误请重新输入：");
            }
        }
        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("?????????????" + limit + "????????????????");
                continue;
            }
            break;
        }

        return line;
    }
}

家庭收支记录程序

FamilyAccount.java

这个程序练手项目，自己写。

import java.util.Scanner;

public class FamilyAccount {

    public static void main(String[] args) {
        boolean isFlag = true;
        //初始化收支明细
        String details = "收支类型\t账户金额\t收支金额\t说  明\n";
        //初始化余额
        int balance = 10000;
        Scanner scan = new Scanner(System.in);
        while (isFlag){
            //程序开始运行就显示记账软件说明
            System.out.println("------------家庭收支记账软件------------");
            System.out.println("             1. 收支明细");
            System.out.println("             2. 登记收入");
            System.out.println("             3. 登记支出");
            System.out.println("             4. 退出");
            System.out.print("             请选择输入1-4：");
            // 获取用户选择1-4
            char selection = Utility.readMenuSelection();
            // 根据用户的选择 分支结构
            switch (selection){
                case '1':
                   //System.out.println("1. 收支明细");
                    System.out.println("------------当前收支明细记录------------");
                    System.out.println(details);
//                    System.out.println("--收支明细待实现--");
                    System.out.println("--------------------------------------");

                    break;
                case '2':
                    //System.out.println("2. 登记收入");
                    System.out.print("本次收入金额：");
                    int income = Utility.readNumber();
                    System.out.print("本次收入说明：");
                    String desc = Utility.readString();
                    balance +=income;
                    System.out.println("------------登记完成------------\n");
                    details += "收入\t\t"+(balance)+"\t"+income+"\t\t"+desc+"\n";

                    break;
                case '3':
                    //System.out.println("3. 登记支出");
                    System.out.print("本次支出金额：");
                    int pay = Utility.readNumber();
                    System.out.print("本次支出说明：");
                    desc = Utility.readString();
                    balance -=pay;
                    System.out.println("------------登记完成------------\n");
                    details += "收入\t\t"+(balance)+"\t"+pay+"\t\t"+desc+"\n";



                    break;
                case '4':
                    //退出程序功能
                    //System.out.println("4. 退出");
                    System.out.print("确认是否退出？Y/N ");
                    char isLoginOut = Utility.readConfirmSelection();
                    if (isLoginOut=='Y'){
                        isFlag = false;
                    }
            }
        }

    }
}