private void addSingleEncoding()

in src/main/java/org/apache/commons/text/AlphabetConverter.java [315:361]
38 lines of code
8 McCabe index (conditional complexity)

    private void addSingleEncoding(final int level,
                                   final String currentEncoding,
                                   final Collection<Integer> encoding,
                                   final Iterator<Integer> originals,
                                   final Map<Integer, String> doNotEncodeMap) {

        if (level > 0) {
            for (final int encodingLetter : encoding) {
                if (!originals.hasNext()) {
                    return; // done encoding all the original alphabet
                }
                // this skips the doNotEncode chars if they are in the
                // leftmost place
                if (level != encodedLetterLength
                        || !doNotEncodeMap.containsKey(encodingLetter)) {
                    addSingleEncoding(level - 1,
                            currentEncoding
                                    + codePointToString(encodingLetter),
                            encoding,
                            originals,
                            doNotEncodeMap
                    );
                }
            }
        } else {
            Integer next = originals.next();

            while (doNotEncodeMap.containsKey(next)) {
                final String originalLetterAsString = codePointToString(next);

                originalToEncoded.put(next, originalLetterAsString);
                encodedToOriginal.put(originalLetterAsString,
                        originalLetterAsString);

                if (!originals.hasNext()) {
                    return;
                }

                next = originals.next();
            }

            final String originalLetterAsString = codePointToString(next);

            originalToEncoded.put(next, currentEncoding);
            encodedToOriginal.put(currentEncoding, originalLetterAsString);
        }
    }