字符串和date之间的相互转换方法

     /**
      * 字符串转Date方法
      * @param dateStr
      * @param format 如yyyy-MM-dd HH:mm:ss等
      * @return
      * @throws Exception
      */
     public static Date stringToDate(String dateStr,String format) throws Exception{
         if(dateStr==null||"".equals(dateStr)){
             throw new Exception("stringToDate:要转换的日期参数为空！");
         }
         Date date = null;
         try{
             SimpleDateFormat sdf = new SimpleDateFormat(format);
             date = sdf.parse(dateStr);
         }catch(Exception e){
             e.printStackTrace();
         }

         return date;
     }
     /**
      * Date转字符串方法
      * @param date
      * @param format 如yyyy-MM-dd HH:mm:ss等
      * @return
      * @throws Exception
      */
     public static String dateToString(Date date,String format) throws Exception{
         if(date==null){
             throw new Exception("dateToString:要转换的日期参数为空！");
         }
         String dateStr = "";
         try{
             SimpleDateFormat sdf = new SimpleDateFormat(format);
             dateStr = sdf.format(date);
         }catch(Exception e){
             e.printStackTrace();
         }

         return dateStr;
     }