Double取整

// Double向上取整，四舍五入
double upvalueB = new java.math.BigDecimal(2.4875).setScale(0,java.math.BigDecimal.ROUND_HALF_UP).doubleValue();
Double mulresult = mul(upvalueB, Double.valueOf(1));
/**
* 向上取整:Math.ceil()
* 向下取整用Math.floor(double a)
*/
System.out.println(mulresult);
System.out.println(Math.ceil(1.0));
System.out.println(Math.ceil(2.345));
System.out.println(Math.ceil(2.6));
System.out.println(Math.floor(2.235));
System.out.println(Math.floor(2.6));