String,Date,Calendar之间的转换，转自String Date Calendar之间的转换

转自http://strongboy789.iteye.com/blog/1551959

1.Calendar 转化 String

Calendar calendat = Calendar.getInstance();

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

String dateStr = sdf.format(calendar.getTime());

 

2.String 转化Calendar

String str="2012-5-27";

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="2012-5-27";

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

Date date= 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();

 

7.String 转成 Timestamp

Timestamp ts = Timestamp.valueOf("2012-1-14 08:11:00");

 

8.Date 转 TimeStamp

SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

String time = df.format(new Date());

Timestamp ts = Timestamp.valueOf(time);

9.Calendar对象获取当前周几

date = (Date) sdf.parse(str);
Calendar calendar = Calendar.getInstance();

calendar.setTime(date);

int day_of_week = calendar.get(Calendar.DAY_OF_WEEK)-1;