Java Regex Negative Lookahead

Question

After looking through the answers that are already on StackOverflow regarding this issue, I settled with the most accurate one I could find:

I went over to gskinner and tested it. I put /foo/(?!.*\\bbar\\b).+ in the pattern input box and the following in the regex match text area:

/foo/abc123doremi

/foo/abc123doremi/bar/def456fasola

Gskinner recognised both of these as matches though so clearly either Gskinner is wrong or the regex pattern above isn't correct. Any thoughts?

Joachim Sauer · Accepted Answer · 2012-12-20 07:55:10Z

5

You are looking for \bbar\b while your text contains /bar/.

What you meant is probably \bbar\b (i.e. /foo/(?!.*\bbar\b).+)

Note that "duplicate the \" is only required inside of Java String literals. That makes writing regexs in Java a bit of a pain.

answered Dec 20, 2012 at 7:55

Joachim Sauer

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