public static boolean wildcardMatch()

in src/main/java/org/apache/commons/io/FilenameUtils.java [1615:1691]
56 lines of code
18 McCabe index (conditional complexity)

    public static boolean wildcardMatch(final String fileName, final String wildcardMatcher, IOCase ioCase) {
        if (fileName == null && wildcardMatcher == null) {
            return true;
        }
        if (fileName == null || wildcardMatcher == null) {
            return false;
        }
        ioCase = IOCase.value(ioCase, IOCase.SENSITIVE);
        final String[] wcs = splitOnTokens(wildcardMatcher);
        boolean anyChars = false;
        int textIdx = 0;
        int wcsIdx = 0;
        final Deque<int[]> backtrack = new ArrayDeque<>(wcs.length);

        // loop around a backtrack stack, to handle complex * matching
        do {
            if (!backtrack.isEmpty()) {
                final int[] array = backtrack.pop();
                wcsIdx = array[0];
                textIdx = array[1];
                anyChars = true;
            }

            // loop whilst tokens and text left to process
            while (wcsIdx < wcs.length) {

                if (wcs[wcsIdx].equals("?")) {
                    // ? so move to next text char
                    textIdx++;
                    if (textIdx > fileName.length()) {
                        break;
                    }
                    anyChars = false;

                } else if (wcs[wcsIdx].equals("*")) {
                    // set any chars status
                    anyChars = true;
                    if (wcsIdx == wcs.length - 1) {
                        textIdx = fileName.length();
                    }

                } else {
                    // matching text token
                    if (anyChars) {
                        // any chars then try to locate text token
                        textIdx = ioCase.checkIndexOf(fileName, textIdx, wcs[wcsIdx]);
                        if (textIdx == NOT_FOUND) {
                            // token not found
                            break;
                        }
                        final int repeat = ioCase.checkIndexOf(fileName, textIdx + 1, wcs[wcsIdx]);
                        if (repeat >= 0) {
                            backtrack.push(new int[] {wcsIdx, repeat});
                        }
                    } else if (!ioCase.checkRegionMatches(fileName, textIdx, wcs[wcsIdx])) {
                        // matching from current position
                        // couldn't match token
                        break;
                    }

                    // matched text token, move text index to end of matched token
                    textIdx += wcs[wcsIdx].length();
                    anyChars = false;
                }

                wcsIdx++;
            }

            // full match
            if (wcsIdx == wcs.length && textIdx == fileName.length()) {
                return true;
            }

        } while (!backtrack.isEmpty());

        return false;
    }