Sarge retry library: meaning of retryOn, escalateOn, and rethrowOn methods

I never used a retry library. I'm testing Sarge (https://github.com/jhalterman/sarge) and the provided examples use the three methods retryOn, escalateOn, and rethrowOn.

However, it is not clear (not even reading the Javadoc) what is the meaning of these methods and when to use them. For example, which is the difference between retryOn and escalateOn?

What does happen when escalateOn is invoked?

How can I see that my method is retried?

Any further information about these topics could be very useful.

Thanks in advance.