Testing with Thread.sleep

Question

What are the recommended approaches to using Thread.sleep() to speed up tests.

I am testing a network library with a retry functionality when connection

Answer 1

Make the sleeping time configurable through a setter, and provide a default value. So in your unit tests, call the setter with a small argument (1 for example), and then execute the method that would call Thread.sleep().

Another similar approach is to make if configurable via a boolean, so that Thread.sleep() isn't called at all if the boolean is set to false.