code: public static ScaleRoundedOperator of(int scale, RoundingMode roundingMode) {
  
  		Objects.requireNonNull(roundingMode);
  
  		if(RoundingMode.UNNECESSARY.equals(roundingMode)) {
  		   throw new IllegalStateException("To create the ScaleRoundedOperator you cannot use the RoundingMode.UNNECESSARY");
  		}
  		return new ScaleRoundedOperator(scale, roundingMode);
  	}
docs: Creates the rounded Operator from scale and roundingMode
  @param scale the scale to be used
  @param roundingMode the rounding mode to be used
  @return the {@link MonetaryOperator} using the scale and {@link RoundingMode} used in parameter
  @throws NullPointerException when the {@link MathContext} is null
  @see RoundingMode