Compute percentage for bigdecimals

Question

I haven't found any native method to do this, so I created my own in a helper class:

public static BigDecimal percentage(BigDecimal base, BigDecimal pct){     return base.multiply(pct).divide(new BigDecimal(100)); } 

But I don't quite like it, I wonder if the API has something similar. The Number class (ancestor of BigDecimal) would be a nice place.

Answer 1

I don't think there is an API for that (I never needed it).
Your solution seams good to me, maybe you just add the constant ONE_HUNDRED:

public static final BigDecimal ONE_HUNDRED = new BigDecimal(100);  public static BigDecimal percentage(BigDecimal base, BigDecimal pct){     return base.multiply(pct).divide(ONE_HUNDRED); } 

probably not that much gain, only if called very often

eventually put it in some Util class...

Answer 2

You may want to implement the division by 100 using BigDecimal.scaleByPowerOfTen(-2).

It adds up if you do it a million times. It is much faster in my experience.

There is also a similar method BigDecimal.movePointLeft(2) - see the other thread for details and decide which one works better for you.