The @Reference annotation defines references to other services made available to the component by the Service Component Runtime.
@reference is used to refer any service registered in your osgi console. So until you declare your class as a service , if you try to refer it using @reference annotation it is going to return you null.
Let us know your use case then community can provide more details
if your component is a service it means if you have declared as @compnent and @service, then yes you can make use of @reference annotation. and include it in another service or component.
