Junit best practice

• Don’t aim at unit testing each method in the SUT. Unit test only the publicly available API.
• When writing unit tests, mimic the behavior of the SUT’s clients.
• Don’t test private methods. Either unit test them indirectly, using the public API, or extract them into separate classes and test those classes instead.
• Don’t hesitate to unit test internal classes as long as you follow the guidelines above
• Test data should  kept and read from a file instead of string variable

https://enterprisecraftsmanship.com/2017/10/23/unit-testing-private-methods/

• JUnit antipatterns
• unit-testing-anti-patterns-catalogue

Unit Test Naving Conventions: 

• 7-popular-unit-test-naming