[preg] matching java variables

[dsaba]

java variables can start with $ or a-z

and followed by a-z, 0-9, and _

 

Here's my attempt at matching them:

~(?<![\$_\w])(?:\$[a-z]|[a-z])[\w_]*~s

 

Yes i'm aware that such patterns can exist within java comments and string statements, but don't worry about this

 

So how can you match it?