如何将BigDecimal舍入小于1(How to round BigDecimal smaller than 1)

 我想将十进制数舍入到最接近的自然数。 例： 
 
public static void main(String[] arguments){
    BigDecimal a=new BigDecimal("2.5");
    BigDecimal b=new BigDecimal("0.5");
    System.out.println(a.round(new MathContext(1,RoundingMode.UP)));
    System.out.println(b.round(new MathContext(1,RoundingMode.UP)));       
    }
 
 预期产出 
 
3
1
 
 实际输出 
 
3
0.5
 
 问题是数字0.5舍入到0.5而不是1如何舍入小于1的BigDecimal 

I want to round decimal number to nearest Natural Number. Example:
 
public static void main(String[] arguments){
    BigDecimal a=new BigDecimal("2.5");
    BigDecimal b=new BigDecimal("0.5");
    System.out.println(a.round(new MathContext(1,RoundingMode.UP)));
    System.out.println(b.round(new MathContext(1,RoundingMode.UP)));       
    }
 
Expected output
 
3
1
 
Real output
 
3
0.5
 
The problem is that number 0.5 is rounded to 0.5 instead of 1 How to Round BigDecimal smaller than 1

原文：https://stackoverflow.com/questions/31918364