Regex to find special characters from a String with some exceptions

I need to write a small regex which should match the occurrences of literal character * when it appears with any other special character. For example, I need to catch all of these occurrences !* )* (* ** *.* . The exception to this is *= and =*, which I want to allow. I tried writing the regex as

\W&&[^=]\*|\*\W&&[^=]

but this doesn't seem to work. Any suggestions? Thanks much for the help.

From stackoverflow

• That one matches all your bad samples:

  (\!\*|\)\*|\(\*|\*\*|\*\.\*)
  

  If you want more than these 4 cases, describe a bit better, what to allow and what to forbid.

  arya : Thanks Johannes for the response. But I was looking for a generic regex which works for any special character. It should catch all of the combination except *= and =*

  arya : Any occurrences of special characters which involve a * are to be caught. Only exception is *= and =*

  Johannes Weiß : define special character

  arya : anything which falls under \W Thanks.

  Johannes Weiß : ah ok, perl regex. Which library do you use? Perl itself?

  arya : I'm using this with Java pattern class

• I think you're looking for a regex with lookbehind and lookahead assertions. Something like:

  (?!=[\=\s])\*(?![\=\s])
  

• try this

  ([^(\W\*)*(\*\W)*]|=\*|\*=)
  

  arya : It works just opposite. It catches nothing but =* and *=

• (\*[^\w=]|[^\w=]\*)
  

  That matches a asterisk followed by any non-word character (other than an equals sign), or a non-word character followed by an asterisk/

  arya : Thanks tj111. That works perfect.