gistfile1.txt

public static void main(String[] args) {
		int year = 1099; // -9999.....9999
		// range check
		
		int date = 12;

		String[] months = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };

		int month = 12; // -100 - +100 --> valid 1..12
		String monthStr = months[month - 1];

		String dateStr = "31";


		boolean validDate = true; // assume date is valid
		if (date < 1) {
			validDate = false;
		}

		// 31
		// 30
		// 28 || 29

		switch (month) {
		case 2:
			if (date > 29) {
				validDate = false;
			}
			break;
		case 1:
		case 3:
		case 5:
		case 7:
		case 12:
			if (date > 31) {
				validDate = false;
			}
			break;
		case 4:
		case 6:
		case 8:
		case 9:
		case 10:
		case 11:
		
			if (date > 30) {
				validDate = false;
			}
			break;
		default: {
			System.out.println("ERROR in month");
			System.exit(1);
			break;
		}
		}

		if (validDate) {
			String yearStr = "" + year; // "-10"
			if (year < 0) {
				yearStr =  "" + (-year) + " BC";
			}
			dateStr = "" + date;
			String message = dateStr + ". " + monthStr + " " + yearStr;
			System.out.println(message);
		} else {
			System.out.println("Error!!");
		}
	}