public static void main(String[] args) throws Exception{//判断某个时间是否为当前时间

         String dataStr="2014-07-24 12:16:04";

         Date createTime=new Date(System.currentTimeMillis());

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

         Date d=dateformat.parse(dataStr);

         Date currentTime=new Date();

         long time=currentTime.getTime()-d.getTime();//当前时间与发送时间的差值

         boolean flag=time<=(long)(60*60*24*1000);

         System.out.println("createTime"+createTime.getTime());

         System.out.println("cureentTime"+currentTime.getTime());

         System.out.println("d"+d.getTime());

         System.out.println("flag"+flag);

     }
     

public static void main(String[] args){

  String date="2099-12-12";

  DateFormat dateformat = new SimpleDateFormat("yyyy-MM-dd");

  Date d1;

  try {

   d1 = dateformat.parse(date);

   Date d2=new Date();

   if(d1.before(d2)){

   System.out.println("字符串的时间早于电脑时间！");

   }

   if(d1.after(d2)){

   System.out.println("字符串的时间晚于电脑时间！");

   }

  } catch (ParseException e) {

   // TODO Auto-generated catch block

   e.printStackTrace();

  }

 }