负正则表达式在Java中落后

Question

I want to match all strings that start with an @ unless they have other characters in front of the @ as well. Simple example: in @one @two and bla@three I want to match @one and @two but not @three . It's for highlighting usernames in a chatroom.

These strings can be anywhere in a sentence (right at the start or in the middle).

I actually thought that (?![a-zA-Z])@[a-zA-Z]+ should work but it still matches @three too.

Answer 1

You don't need a regex look around, you can use a simple regex like this:

\B@\w+

Working demo