将日期格式化为字符串示例：

SimpleDateFormat sdf = new SimpleDateFormat("dd/M/yyyy");
String date = sdf.format(new Date()); 
System.out.println(date); //Prints 26/10/2015

以下是我们可以使用的最常见模式字母的列表。

y   = year   (yy or yyyy)
M   = month  (MM)
d   = day in month (dd)
h   = hour (0-12)  (hh)
H   = hour (0-23)  (HH)
m   = minute in hour (mm)
s   = seconds (ss)
S   = milliseconds (SSS)
z   = time zone  text        (e.g. Pacific Standard Time...)
Z   = time zone, time offset (e.g. -0800)

例如，

yyyy-MM-dd           	(2015-12-31)
dd-MM-YYYY           		(31-10-2015)
yyyy-MM-dd HH:mm:ss  		(2015-12-31 23:59:59)
HH:mm:ss.SSS         		(23:59.59.999)
yyyy-MM-dd HH:mm:ss.SSS   	(2015-12-31 23:59:59.999)
yyyy-MM-dd HH:mm:ss.SSS Z   (2015-12-31 23:59:59.999 +0100)