public static NameAbbreviator getAbbreviator()

in log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/NameAbbreviator.java [48:135]
61 lines of code
17 McCabe index (conditional complexity)

    public static NameAbbreviator getAbbreviator(final String pattern) {
        if (pattern.length() > 0) {
            //  if pattern is just spaces and numbers then
            //     use MaxElementAbbreviator
            final String trimmed = pattern.trim();

            if (trimmed.isEmpty()) {
                return DEFAULT;
            }

            final NameAbbreviator dwa = DynamicWordAbbreviator.create(trimmed);
            if (dwa != null) {
                return dwa;
            }

            boolean isNegativeNumber;
            final String number;

            // check if number is a negative number
            if (trimmed.length() > 1 && trimmed.charAt(0) == '-') {
                isNegativeNumber = true;
                number = trimmed.substring(1);
            } else {
                isNegativeNumber = false;
                number = trimmed;
            }

            int i = 0;

            while (i < number.length() && number.charAt(i) >= '0' && number.charAt(i) <= '9') {
                i++;
            }

            //
            //  if all blanks and digits
            //
            if (i == number.length()) {
                return new MaxElementAbbreviator(
                        Integers.parseInt(number),
                        isNegativeNumber ? MaxElementAbbreviator.Strategy.DROP : MaxElementAbbreviator.Strategy.RETAIN);
            }

            final List<PatternAbbreviatorFragment> fragments = new ArrayList<>(5);
            char ellipsis;
            int charCount;
            int pos = 0;

            while (pos < trimmed.length() && pos >= 0) {
                int ellipsisPos = pos;

                if (trimmed.charAt(pos) == '*') {
                    charCount = Integer.MAX_VALUE;
                    ellipsisPos++;
                } else if (trimmed.charAt(pos) >= '0' && trimmed.charAt(pos) <= '9') {
                    charCount = trimmed.charAt(pos) - '0';
                    ellipsisPos++;
                } else {
                    charCount = 0;
                }

                ellipsis = '\0';

                if (ellipsisPos < trimmed.length()) {
                    ellipsis = trimmed.charAt(ellipsisPos);

                    if (ellipsis == '.') {
                        ellipsis = '\0';
                    }
                }

                fragments.add(new PatternAbbreviatorFragment(charCount, ellipsis));
                pos = trimmed.indexOf('.', pos);

                if (pos == -1) {
                    break;
                }

                pos++;
            }

            return new PatternAbbreviator(fragments);
        }

        //
        //  no matching abbreviation, return defaultAbbreviator
        //
        return DEFAULT;
    }