private String convertGlobToRegex()

in core/src/main/java/org/apache/brooklyn/core/workflow/steps/variables/TransformReplace.java [106:193]
86 lines of code
32 McCabe index (conditional complexity)

    private String convertGlobToRegex(String pattern, boolean isGreedy) {
        StringBuilder sb = new StringBuilder(pattern.length());
        int inGroup = 0;
        int inClass = 0;
        int firstIndexInClass = -1;
        char[] arr = pattern.toCharArray();
        for (int i = 0; i < arr.length; i++) {
            char ch = arr[i];
            switch (ch) {
                case '\\':
                    if (++i >= arr.length) {
                        sb.append('\\');
                    } else {
                        char next = arr[i];
                        switch (next) {
                            case ',':
                                // escape not needed
                                break;
                            case 'Q':
                            case 'E':
                                // extra escape needed
                                sb.append('\\');
                            default:
                                sb.append('\\');
                        }
                        sb.append(next);
                    }
                    break;
                case '*':
                    if (inClass == 0)
                        sb.append(".*"+(isGreedy ? "" : "?"));
                    else
                        sb.append('*');
                    break;
                case '?':
                    if (inClass == 0)
                        sb.append('.');
                    else
                        sb.append('?');
                    break;
                case '[':
                    inClass++;
                    firstIndexInClass = i+1;
                    sb.append('[');
                    break;
                case ']':
                    inClass--;
                    sb.append(']');
                    break;
                case '.':
                case '(':
                case ')':
                case '+':
                case '|':
                case '^':
                case '$':
                case '@':
                case '%':
                    if (inClass == 0 || (firstIndexInClass == i && ch == '^'))
                        sb.append('\\');
                    sb.append(ch);
                    break;
                case '!':
                    if (firstIndexInClass == i)
                        sb.append('^');
                    else
                        sb.append('!');
                    break;
                case '{':
                    inGroup++;
                    sb.append('(');
                    break;
                case '}':
                    inGroup--;
                    sb.append(')');
                    break;
                case ',':
                    if (inGroup > 0)
                        sb.append('|');
                    else
                        sb.append(',');
                    break;
                default:
                    sb.append(ch);
            }
        }
        return sb.toString();
    }