Then you need to pass the object around.
You say that you want to create an object, but you can't do this without context. Where is the object created? If you want to do all of this in the same method, you first create the object using the new keyword, then you pass it to the appropriate method of class A, and then you pass it to the appropriate method of class B.
Your original code differs from this in that you first call the method of A which creates its own object.
You should first create r, and then pass it to currentHour().