Using Mockito for mocking services

Let's see following quote about the role of mocking:

"Mockito is a mocking framework that tastes really good. It lets you write beautiful tests with a clean & simple API. Mockito doesn't give you hangover because the tests are very readable and they produce clean verification errors."

                                             –  Mockito. Mockito Framework Site. N.p., n.d. Web. 28 Apr. 2017.

When running tests, it is sometimes necessary to mock certain components within your application context. For example, you may have a facade over some remote service that is unavailable during development. Mocking can also be useful when you want to simulate failures that might be hard to trigger in a real environment. Let's see the following test class where I have used Mocking:

package com.dineshonjava.accountservice; 
 
import static org.hamcrest.CoreMatchers.is; 
import static org.hamcrest.CoreMatchers.notNullValue; 
import static org.junit.Assert.assertFalse...