I've noticed the webpage of this repository doesn't explain how to leave the previous one :
https://googleapis.dev/java/google-api-client/latest/com/google/api/client/googleapis/auth/oauth2/GoogleCredential.html

Is your feature request related to a problem? Please describe.
Yes, I can't find the appropriate functions that match the previous ones. There is no documentation.

Describe the solution you'd like
To have such explanation.

Describe alternatives you've considered
Maybe write it on the old repository ?

I requested this here for the sample I've found, but it hasn't been updated for a very long time. I can't find a similar sample by Google

Additional context
The code I use (here) is very similar and based on what I've found of using the repository to reach the old API, here.

Would be very appreciated if you could tell me at least for these cases how to use them, or provide a nice sample that provides the same thing, of reaching People API.