Calendar和Date的转化

(1) Calendar转化为Date
Calendar cal=Calendar.getInstance();
Date date=cal.getTime();

(2) Date转化为Calendar
Date date=new Date();
Calendar cal=Calendar.getInstance();
cal.setTime(date); 

 

Date和 String 的转换

（1）Date 转String 

Date d =new Date();

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:SS");

String str = sdf.format(d);

(2)String 转Date 

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:SS");

String d1 = "2016-11-23 13:36:10";
Date d2 = sdf.parse(d1);