double保留两位小数（四舍五入）

public static Double roundDouble(double val, int precision) {
		Double ret = null;
		try {
			double factor = Math.pow(10, precision);
			ret = Math.floor(val * factor + 0.5) / factor;
		} catch (Exception e) {
			e.printStackTrace();
		}

		return ret;
	}

 

val为处理double 数字，precsion为保留小数位数。