JUnit tests for POJOs

java junit pojo
Ryan Thames picture Ryan Thames · Mar 23, 2009 · Viewed 51.5k times · Source

I work on a project where we have to create unit tests for all of our simple beans (POJOs). Is there any point to creating a unit test for POJOs if all they consist of is getters and setters? Is it a safe assumption to assume POJOs will work about 100% of the time?

Duplicate of - Should @Entity Pojos be tested?

See also

Is it bad practice to run tests on a DB instead of on fake repositories?

Is there a Java unit-test framework that auto-tests getters and setters?

Answer

Uncle Bob picture Uncle Bob · Mar 23, 2009

The rule in TDD is "Test everything that could possibly break" Can a getter break? Generally not, so I don't bother to test it. Besides, the code I do test will certainly call the getter so it will be tested.

My personal rule is that I'll write a test for any function that makes a decision, or makes more than a trivial calculation. I won't write a test for i+1, but I probably will for if (i<0)... and definitely will for (-b + Math.sqrt(b*b - 4*a*c))/(2*a).

BTW, the emphasis on POJO has a different reason behind it. We want the vast quantity of our code written into POJOs that don't depend on the environment they run in. For example, it's hard to test servlets, because they depend upon executing within a container. So we want the servlets to call POJOs that don't depend on their environment and are therefore easy to test.

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