Infinite recurssion when using Regex to extract column names from SQL

[ver sd]

I am trying to get all the columns within a SQL query (including the sub selects). When the code hits matcher.find(). i get the following exception:

Exception in thread "main" java.lang.StackOverflowError
at java.util.regex.Pattern$Branch.match(Pattern.java: 4530)
at java.util.regex.Pattern$GroupHead.match(Pattern.ja va:4570)

I am not sure where in the regex is causing the inifinite recursion.
Can anyone shed light on this?


String regex = "^select(([^\\(]|\\([^\\(]+\\))*)from";
Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | Pattern.DOTALL | Pattern.MULTILINE);
Matcher matcher = pattern.matcher(sql);
if (matcher.find()) {
// Get all groups for this match
for (int i = 0; i <= matcher.groupCount(); i++) {
String groupStr = matcher.group(i);
}
}

Any input on this is helpful.
Thanks in advance.

[Ilja Preuss]

Please don't post the same question in multiple forums. It creates duplicate conversations and thereby wastes the time of the people trying to help you. See http://faq.javaranch.com/view?CarefullyChooseOneForum

Thanks.