How to properly use switching between iframes in Page obj. pattern?

Question

Java

Hello, tell me how to use switching between frames in page ob. pattern?
because there is an application in which at a certain stage of the case you need to switch between 6 frames. I would like to simplify this procedure. now I declare the switching function in the same class as the test itself.
Thanks in advance.

Answer 1

An example page, please?
and an example of splitting your classes