java.lang.ClassCastException: java.math.BigDecimal cannot be cast to java.lang.Integer

mysql中通过统计函数返回值是BigDecimal，不能使用Integer或者String 接收，否则报错

		SELECT
		SUM(CASE WHEN b.bill_state =1 THEN b.money ELSE 0 END ) AS pay,
		SUM(CASE WHEN b.bill_state !=1 THEN b.money ELSE 0 END ) AS noPay
		FROM bl_bill b
		INNER JOIN bl_room r
		ON b.room_id = r.id
		INNER JOIN bl_unit un
		ON r.unit_id = un.id
		INNER JOIN bl_house house
		ON un.house_id = house.id
		INNER JOIN bl_region re
		ON house.region_id = re.id		



Map getMonthFee();

java.lang.ClassCastException: java.math.BigDecimal cannot be cast to java.lang.String

或者 

java.lang.ClassCastException: java.math.BigDecimal cannot be cast to java.lang.Integer

处理方式可以将取到的Object数据使用Integer.valueOf(s)方法转换成Integer

Map monthFee = indexCountService.getMonthFee();

Integer monthPay = monthFee.get("pay") == null ? 0 : Integer.valueOf(monthFee.get("pay")+"");