JUnit VS AssertJ

Because I only wanna use the cmd java test, so I chose Junit4 which supports Plain-old JAR. I did test according to the Getting started document. But when I ran the javac -cp .:junit-4.XX.jar:hamcrest-core-1.3.jar CalculatorTest.java I got the error message CalculatorTest.java:4: error: package main does not exits. I tried to reorganize the folder and set Path according to others' experience 1, 2, but it still did not work.

Oops, another error. This is why we should read the manual 😅.

JUnit4

Delete those imports and remove the junit-jupiter-api dependency. Follow the instructions for JUnit 4.

Quite a lot of Java dependencies bring Junit 4 or Junit vintage engine as a transitive dependency.

The AHTest039.json file is the actual test. My testRunner() method (no relation to JUnit test runners) reads that JSON file, processes it, and asserts that the test passed. So my test class consists of a few Java methods, and what is essentially a list of JSON files to process.

Maybe not the feedback you want, but would you consider developing something that looks like plain old (and frankly beautiful) AssertJ?

AssertJ - fluent assertions

AssertJ https://github.com/assertj/assertj

Truth or AssertJ for easier assertions in tests with better exceptions

While we are at it: AssertJ is very powerful for writing assertions.

In OO you can make beautiful DSLs that allow really declarative use within that domain, e.g. test assertions in AssertJ, but everybody in the OO world is sensible enough to not try and claim OO as such being declarative. I guess they don't feel a need to try to prove the superiority of the paradigm.

AssertJ comes with a variety of assertions that can be chained together and are specific to the type of your "actual" variable.

At any rate it comes from a library called assertj.

While Hamcrest add some fluentidity to unit tests ä, I prefer the fluent assertions of AssertJ.