OT ? - Validating POSIX Regular Expression in Java

Hi all,

 I know it's not directly the purpose of this list, so I apologize, but 
I think you guys are the ones who can help me :-)

My web site offers a search which supports regular expression (POSIX).  
I'm looking for a way to validate the regular expression in the 
application before sending it the the DB.  For now Postgresql throwing 
an error on invalid regular expression.

I tried with  the gnu-regexp frameworks,  It works partly but it's not 
full proof since an invalid caracter class like  [[:awefaewf:]]* is not 
flagged as an error but causes an error with Postgresql.

Any help on this matter will be appreciated.  I'm sure it's a common 
problem and have been addressed before ... I searched but haven't found 
the answer yet.

Thanks for your help

/David

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