private static void format_exception()

in metrics-core/src/benchmarks/java/com/amazon/metrics/DoubleFormat.java [72:124]

• 35 lines of code
• 10 McCabe index (conditional complexity)

    private static void format_exception(Appendable sb, double value) throws IOException {
        // store the sign of the input, get the input as a positive number w/o sign
        boolean negative = (value < 0);
        double positiveValue = Math.abs(value);

        // if value is too large for us to handle, revert to builtin formatter
        if (positiveValue > TOO_BIG_THRESHOLD) {
            handleInputTooBig(sb, value);
            return;
        }

        // Separate the number into whole number and fraction components.
        // Scale the fraction component based upon the max number of digits to display.
        // Additionally, store remaining (unprinted) fraction amount for use in rounding
        // decisions.
        int whole = (int) positiveValue;
        double tmp = (positiveValue - whole) * MAX;
        int fraction = Math.abs((int) tmp);
        double diff = tmp - fraction;

        int comp = Double.compare(diff, 0.5);
        if(comp > 0) {
            // round up
            fraction++;
        } else if(comp == 0 && ((fraction == 0) || (fraction & 1) != 0)) {
            // round up
            fraction++;
        }

        // if rounding has pushed us up to the next whole number, adjust:
        // clear fraction amount and increment whole number
        if(fraction >= MAX) {
            fraction = 0;
            whole++;
        }

        int leadingZeros = countLeadingZeros(fraction);
        fraction = trimTrailingZeros(fraction);

        // Once the double value has been appropriately split and rounded, write as a string
        if(negative) {
            sb.append('-');
        }
        sb.append(Integer.toString(whole));

        if(fraction != 0) {
            sb.append('.');
            for(int i = 0; i < leadingZeros; i++) {
                sb.append('0');
            }
            sb.append(Integer.toString(fraction));
        }
    }