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Java regex pattern to match word or phrase

Answer 1

A:

You've got (IHS) - a group - where you want $IHS$ as the literal brackets.

cyborg 2010-01-05 23:24:42

Answer 2

A:

You need to escape the parentheses

\bIntegrated\s+Health\s+System\s+\(IHS\)\b

Parentheses delimit a capture group. To match a literal set of parentheses, you can escape them like this 

mopoke 2010-01-05 23:24:57

Answer 3

+1 A:

1) escape the parens, otherwise they are capturing and group metacharacters, not literal parenthesis 

2) remove the final \b you can't use a word boundary after a literal ), since ) is not considered part of a word.

\bIntegrated\s+Health\s+System\s+\(IHS\)\W

Paul Creasey 2010-01-05 23:26:56

Okay, how do I indicate the trailing boundary then, so it does not match something like \bIntegrated\s+Health\s+System\s+$IHS$testingI need to make sure it only matches the whole phrase and not some string that starts with this phrase.

Eqbal 2010-01-05 23:35:41

you could use \W which is the same as [^\w] or [^a-bA-B0-9_] (not sure exactly what it includes in java), or you could create you own character class (or negated class) to specify what does or does not indicate a match. I've updated the example with \W which will likely work pretty well.

Paul Creasey 2010-01-05 23:48:37

Thanks, \W seems to work pretty well so far combined with grouping to extract the matched phrase minus the non-word character that follows.

Eqbal 2010-01-06 00:00:48

If you want to allow the match at the end of the string you would have to say `($|\W)`. I'm not sure it's so important though, are you likely to have strings like `Integrated Health Systems (IHS)foo`? The close bracket is almost invariably followed by space or punctuation.

bobince 2010-01-06 00:16:00

Okay, here is my final regex pattern:`"(\\b|\\W)(" + phrase + ")($|\\W)"`Using the group 2 to get the matched phrase.

Eqbal 2010-01-06 01:17:01

Hmm. That causes problem if the phrase begins with a "(". So modified it to `"(^|\\W)(" + phrase + ")($|\\W)"`

Eqbal 2010-01-06 01:27:49

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Java regex pattern to match word or phrase

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