Re: buggy regexp
On 31.05.2007 16:33, ilyabo@xxxxxxxxx wrote:
Hello all!
The following line hangs in Java:
Pattern.matches("((<BR>)|([^<>]+))*", "aaaaaaaaaaaaaaaaaaaaaaaa
<BR><Bx>")
What's wrong with the regular expression?
You nest "+" and "*" which can lead to bad backtracking (which you seem
to experience). If you wait long enough you'll see the result.
If you just want to test for the presence of "<BR>" you can do this:
boolean match = str.indexOf("<BR>") != -1;
Or as regexp
Pattern p = Pattern.compile("<BR>");
boolean match = p.matcher(s).find();
Kind regards
robert
.
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