NIFI-6117: Fix BIGINT handling in DataTypeUtils

[mattyb149]

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[ijokarumawak]

Thanks @mattyb149 for your quick fix!

Other numerical types use isNumberTypeCompatible method for compatibility check. Can we use that one for BigInt, too?

[ijokarumawak]

@mattyb149 In order to align with other numeric types, I suggest separating the existing isIntegral method like below.

    public static boolean isBigIntTypeCompatible(final Object value) {
        return isNumberTypeCompatible(value, s -> isIntegral(s))
    }

    // We need something similar to isIntegral, but the value can be larger than the max long.
    // So let's extract the String validation part like this.
    private static boolean isIntegral(final String value) {
        if (value == null || value.isEmpty()) {
            return false;
        }

        int initialPosition = 0;
        final char firstChar = value.charAt(0);
        if (firstChar == '+' || firstChar == '-') {
            initialPosition = 1;

            if (value.length() == 1) {
                return false;
            }
        }

        for (int i = initialPosition; i < value.length(); i++) {
            if (!Character.isDigit(value.charAt(i))) {
                return false;
            }
        }

        return true;
    }

    // This one works as is. But we can use the same isIntegral(String) part.
    private static boolean isIntegral(final String value, final long minValue, final long maxValue) {

        if (!isIntegral(value)) {
            return false;
        }

        try {
            final long longValue = Long.parseLong(value);
            return longValue >= minValue && longValue <= maxValue;
        } catch (final NumberFormatException nfe) {
            // In case the value actually exceeds the max value of a Long
            return false;
        }
    }

[ijokarumawak]

@mattyb149 just wanted to check. Are you still working on this? Thanks!

[mattyb149]

I want to finish this out but haven't had the time, I can try to incorporate your comments this week, or if you'd like to do so, I can patch and review/merge in place, totally up to you :)

[ijokarumawak]

Ok, I submitted a PR to your branch. Please check it. I'm +1 with this PR once mine is merged too :)

[mattyb149]

+1 LGTM, thanks for getting this across the finish line. Merging to master