Java regular expression optimization tips

I wanted to post this as a comment to Tim Pietzcker's answer but figured there won't be enough space there. While the regex given by Tim avoids catastrophic backtracking to some extent, it still has nested quantifiers which can cause a problem with a specific input text and cause StackOverflowException as shown below. I want to repeat that this answer is just a demonstration of the weird StackOverflowException and it is not supposed to be a rant on anyone's answer.

    public class CatastrophicBacktrackingRegexRemedy {
    public static void main(String[] args) {
        regexWithNoStackOverflow();
        regexCausingStackOverflow();
    }

    /**
     * Stackoverflow is caused on a specific input, 
     * In this case "A " repeated about 1000 times.
     * This is because of the nested quantifier (?:[\\ ][\\w-]+)*
     */
    private static void regexCausingStackOverflow() {
        StringBuilder subjectStringBuilder = new StringBuilder();
        String subjectString = "A ";
        for (int i = 0; i < 1000; i++) {
            subjectStringBuilder.append(subjectString);
        }
        subjectStringBuilder.append("A");
        //2001 character input
        System.out.println("Input length :" + subjectStringBuilder.length());
        //This causes stackoverflow exception on a string with 2001 characters 
        //on my JVM
        boolean foundMatch = subjectStringBuilder.toString().matches(
                "(?ix)        # Case-insensitive, multiline regex:\n"
                + "^          # Start of string\n"
                + "(?!        # Assert that it's impossible to match\n"
                + " .*        # any number of characters\n"
                + " (?:--|__) # followed by -- or __\n"
                + ")          # End of lookahead assertion\n"
                + "[A-Z0-9]+  # Match A-Z, a-z or 0-9\n"
                + "(?:        # Match the following:\n"
                + " [\\ ]     # a single space\n"
                + " [\