regexp, don't match url

I have to match words longer than 30 characters, but these words can't be urls.

I tried to do this, but doesn't work fine:

(?<!ftp)([^\s\t\r\n<>]{30})

I have a few points:

• Your regular expression can match ftp://example.com because you are using a lookbehind, which sees nothing before the first f. Use a lookahead instead.
• Also you need to ensure that you match entire words, otherwise you can matching part way into a URL.
• \s includes \t, \n, etc... so the latter is redundant.
• Longer than 30 characters means 31 or more characters, i.e. {31,}.

Try this instead:

(?<![^\s<>])(?!ftp)([^\s<>]{31,})(?![^\s<>])