java 日期操作

一、获取2015-09-18 00:00:00.0

     

Calendar currentCalendar=Calendar.getInstance();
Date currentDateTime=currentCalendar.getTime();
Calendar cl=Calendar.getInstance();
cl.set(currentCalendar.get(Calendar.YEAR), currentCalendar.get(Calendar.MONTH), currentCalendar.get(Calendar.DATE),0, 0, 0);
SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.S");
SimpleDateFormat sdf2=new SimpleDateFormat("yyyy-MM-dd");
String str=sdf.format(cl.getTime());
System.out.println(sdf.format(sdf2.parse(str)));

二、获取2个时间的 差多少天

Date currentDateTime=Calendar.getInstance().getTime();
Date dataCreateDate=Calendar.getInstance().getTime();
long diff = dataCreateDate.getTime() - currentDateTime.getTime();
long days = diff / (1000 * 60 * 60 * 24);