Sting to Date 格式化时间

try {
			String str = "2011-09-21 17:31:48";
			// 请注意和上面str的格式保持一致性。
			SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
			Date date = new Date();
			date = sdf.parse(str);
			SimpleDateFormat sdft = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
			System.out.println("时间是 :" + sdft.format(date));
		} catch (ParseException e) {
			e.printStackTrace();
		}

		Calendar calendar = new GregorianCalendar();
		System.out.println("年: " + calendar.get(Calendar.YEAR));
		System.out.println("月: " + (calendar.get(Calendar.MONTH) + 1));
		System.out.println("日: " + calendar.get(Calendar.DAY_OF_MONTH));
		System.out.println("时: " + calendar.get(Calendar.HOUR_OF_DAY));
		System.out.println("分: " + calendar.get(Calendar.MINUTE));
		System.out.println("秒: " + calendar.get(Calendar.SECOND));
		System.out.println("毫秒: " + calendar.get(Calendar.MILLISECOND));