//获取哪一天

     public static int getDay(Date date) {

         Calendar calendar = Calendar.getInstance();

         calendar.setTime(date);

         return calendar.get(Calendar.DATE);

     }

     /**

      * 返回日期的月份，1-12,即yyyy-MM-dd中的MM

      *

      * @param date

      * @return

      */

     public static int getMonth(Date date) {

         Calendar calendar = Calendar.getInstance();

         calendar.setTime(date);

         return calendar.get(Calendar.MONTH) + 1;

     }

     /**

      * 返回日期的年,即yyyy-MM-dd中的yyyy

      *

      * @param date

      *            Date

      * @return int

      */

     public static int getYear(Date date) {

         Calendar calendar = Calendar.getInstance();

         calendar.setTime(date);

         return calendar.get(Calendar.YEAR);

     }

     public static int calDiffMonth(String startDate,String endDate) {

         int result=0;

         try {

             SimpleDateFormat sfd=new SimpleDateFormat("yyyyMMdd");

             Date start = sfd.parse(startDate);

             Date end = sfd.parse(endDate);

             int startYear=getYear(start);

             int startMonth=getMonth(start);

             int startDay=getDay(start);

             int endYear=getYear(end);

             int endMonth=getMonth(end);

             int endDay=getDay(end);

             Calendar calendar2= Calendar.getInstance();

             calendar2.setTime(start);

             int maxDay = calendar2.getActualMaximum(Calendar.DAY_OF_MONTH);//获取起始日期所在月的最后一天

             Calendar calendar3 = Calendar.getInstance();

             calendar3.setTime(end);

             int maxEndDay = calendar3.getActualMaximum(Calendar.DAY_OF_MONTH);//获取结束日期所在月的最后一天

             if(startDay == maxDay){//起始日期是在月末

                 if(maxEndDay==endDay){

                     result=(endYear-startYear)*12+endMonth-startMonth;

                 }else {

                     result=(endYear-startYear)*12+endMonth-startMonth-1;

                 }

             }else if(endDay==maxEndDay){//结束日期是在月末

                 result=(endYear-startYear)*12+endMonth-startMonth;

             }else {

                 if (endDay >= startDay) {

                     result=(endYear-startYear)*12+endMonth-startMonth;

                 }else {

                     result=(endYear-startYear)*12+endMonth-startMonth-1;

                 }

             }

         } catch (Exception e) {

             e.printStackTrace();

         }

         return result;

     }

     public static void main(String[] args) {

         int i = calDiffMonth("20171030", "20180228");

         System.out.println(i);

     }