JAVA基础家庭记账软件案例(循环，分支，基本数据类型)

JAVA基础家庭记账软件

		Scanner input = new Scanner(System.in);
		boolean loop = true;//是否循环
		String details = "收支\t\t收支金额\t\t账户金额\t\t说明\t\n";
		int money = 10000;//初始本金
		boolean haveIn = false;//是否有登记
		do{
			//循环操作
			System.out.println("\n-------------------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-------------------\n");
			System.out.print("请选择(1-4): ");
			//读取用户键盘录入
			char key = input.next().charAt(0);
			//判断用户输入内容
			switch(key){
				case '1'://收支明细
					if(!haveIn){
						System.out.println("暂无收支记录!");
						continue;//下面都不走了 继续下次循环
					}
					System.out.println("-------------------当前收支明细记录--------------");
					System.out.println(details);
					break;
				case '2'://登记收入
					System.out.print("本次收入金额: ");
					int balance = input.nextInt();
					System.out.println();
					System.out.print("本次收入说明: ");
					String account = input.next();
					System.out.println();
					//登记步骤
					money += balance;
					//更新details
					details += "收入\t\t"+balance+"\t\t"+money+"\t\t"+account+"\t\n";
					System.out.println("-------------------当前收支明细记录--------------");
					System.out.println(details);
					haveIn = true;//更新标志
					break;
				case '3'://登记支出
					System.out.print("本次支出金额: ");
					int outbalance = input.nextInt();
					System.out.println();
					System.out.print("本次支出说明: ");
					String outaccount = input.next();
					System.out.println();
					//登记步骤
					money -= outbalance;
					//更新details
					details += "支出\t\t"+outbalance+"\t\t"+money+"\t\t"+outaccount+"\t\n";
					System.out.println("-------------------当前收支明细记录--------------");
					System.out.println(details);
					haveIn = true;//更新标志
					break;
				case '4'://退出
					System.out.print("确定要退出吗？Y/N: ");
					for(;;){
						char isExit = input.next().toUpperCase().charAt(0);
						if(isExit == 'Y'){
							loop = false;//结束大循环
							break;
						}
						if(isExit == 'N'){
							break;//退出小循环
						}
						System.out.print("输入错误，请重新输入: ");
					}
			}
		}while(loop);