Date、String、Calendar类型之间的转化

1.Calendar 转化 String 

 //获取当前时间的具体情况,如年,月,日,week,date,分,秒等 
        Calendar calendat = Calendar.getInstance();

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
String dateStr = sdf.format(calendar.getTime());

2.String 转化Calendar

String str="2010-5-27";
SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");

Date date =sdf.parse(str);

Calendar calendar = Calendar.getInstance();

calendar.setTime(date);

3.Date 转化String

SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");

String dateStr=sdf.format(new Date());

4.String 转化Date 
String str="2010-5-27";

SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd");

Date birthday = sdf.parse(str);

5.Date 转化Calendar

Calendar calendar = Calendar.getInstance();
calendar.setTime(new java.util.Date());

6.Calendar转化Date

Calendar calendar = Calendar.getInstance();
java.util.Date date =calendar.getTime();