JAVA获取每个月的天数

            String month = vo.getM_MONITORMONTH();

            int year = Integer.parseInt(month.substring(0, month.indexOf('-')));

            int mth = Integer.parseInt(month.substring(month.indexOf('-')+1));

            Calendar calendar = Calendar.getInstance(); 

            calendar.clear();    //在使用set方法之前，必须先clear一下，否则很多信息会继承自系统当前时间

            calendar.set(Calendar.YEAR,year);   

            calendar.set(Calendar.MONTH,mth-1);  //Calendar对象默认一月为0          

            int endday = calendar.getActualMaximum(Calendar.DAY_OF_MONTH);//获得本月的天数