Java实现日期的加减运算

方法1:

   Calendar calendar=Calendar.getInstance();  
   calendar.setTime(new Date());
   System.out.println(calendar.get(Calendar.DAY_OF_MONTH)); 
   calendar.set(Calendar.DAY_OF_MONTH,
                calendar.get(Calendar.DAY_OF_MONTH)+1); 
   System.out.println(calendar.get(Calendar.DATE));



方法2:

   Date d=new Date();  
   SimpleDateFormat df=new SimpleDateFormat("yyyy-MM-dd");  
   System.out.println("今天的日期："+df.format(d));  
   System.out.println("两天前的日期：" + df.format(new Date(
              d.getTime() - 2 * 24 * 60 * 60 * 1000)));  
   System.out.println("三天后的日期：" + df.format(new Date(
              d.getTime() + (long)3 * 24 * 60 * 60 * 1000)));