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• TestNG: As testing framework. We decided to move from junit to testNG some years ago when junit seemed to be stuck
• Mockito: To allow easy mock-based testing. 
• Hamcrest: To allow to read the asserts in a human-understandable way.

Testing a spring-based service or standard Java class

Actually this is the situation that you very often will write unit tests. You created or extended a service and want to ensure that it is working. So this is what you want to do:

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