How to pass Context to OkHttp3?

Question

Java

Hello, I am a complete newbie to java.
There is an example of using PersistentCookieJar on github:

ClearableCookieJar cookieJar =
                new PersistentCookieJar(new SetCookieCache(), new SharedPrefsCookiePersistor(context));

I read several articles about context and what it is. Roughly understood, but absolutely do not understand how to use it in this case. What exactly to transmit?
Tried like this:
import android.content.Context;
Then further in the class I declared:
private Context context;
Also tried:
private Context context = getApplicationContext();
None of this works - the app just crashes.
Can you please tell me how to declare this context correctly and how to use it in this case?