Support \Q\E quotation

[vkopichenko]

It would be nice to provide possiblity to escape some parts of regex from generation without need to escape each special character one by one.
For example I'd like to use

minion_\d{3}\Q@gru.evil\E

instead of

minion_\d{3}\@gru\.evil

Here is a workaround code to transform the former to latter:

    private static String requote(String regex) {
        final Pattern PATTERN_QUOTED = Pattern.compile("\\\\Q(.*?)\\\\E");
        // http://stackoverflow.com/questions/399078/what-special-characters-must-be-escaped-in-regular-expressions
        // adding "@" prevents StackOverflowError inside generex: https://github.com/mifmif/Generex/issues/21
        final Pattern PATTERN_SPECIALS = Pattern.compile("[.^$*+?(){|\\[\\\\@]");
        StringBuilder sb = new StringBuilder(regex);
        Matcher matcher = PATTERN_QUOTED.matcher(sb);
        while (matcher.find()) {
            sb.replace(matcher.start(), matcher.end(), PATTERN_SPECIALS.matcher(matcher.group(1)).replaceAll("\\\\$0"));
            //matcher.reset();
        }
        return sb.toString();
    }

[mifmif]

It's a nice feature, I will work on this point, you can fork the project and add this feature, then i will merge your request.

[mifmif]

This feature is now supported

[vkopichenko]

The initial requote implementation here were vulnerable to some problems:

• no escape for &"<#~ automaton special chars
• incorrect handling of multiple adjacent quote groups
• no support for multiline patterns

These were fixed in PR #48.