I think this returns `void` and not `null`. Therefore the `@return` statement can be dropped.

See http://www.phpdoc.org/docs/latest/for-users/phpdoc/tags/return.html:

> It is RECOMMENDED when documenting to use this tag with every function and method. Exceptions to this recommendation are:
> - constructors, the @return tag MAY be omitted here, in which case @return self is implied.
> - functions and methods without a `return` value, the @return tag MAY be omitted here, in which case @return void is implied.