java 根据日期获取某个月有多少天的问题

public String getDaysOfMonth(Date date) {

       Calendar calendar =(); 

        (date); 

        (Calendar.DAY_OF_MONTH)+"";

    }

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

Date time_end_date=(model.getCreate_time_end());

String endTime_end=(time_end_date);

//方法2

//获取某月多少天

    public int getDaysByYearMonth(int month) {        

        Calendar a =(); 

        //(,year); 

        (, month- 1); 

        (, 1); 

        (,-1); 

        int maxDate =(); 

        return maxDate; 

    }