Unit-testing - how to start with it? [duplicate]

This question already has answers here: Getting Started with Unit Testing (7 answers) 开发者_开发问答 Closed 6 years ago.

at the moment I'm developing in a more "uncool" kind: I write my stuff and see if this works with manual interaction. (For the most time I'm writing java based webapps)

I know that unit-testing would cut some of the bugs I meet in devtime but to be honest: I dont know how go with unittesting. Especially I don't really have a clue how I test respectively split my code in small units which can ran in Junit or something.

I really would appreciate it if someone could point me literature, blog or tutorial to get a little deeper into this topic or much better: Maybe you can share some of your experiences.

Cheers and regards

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Netbeans will automatically generate JUnit tests (I think Eclipse and other IDEs also do this).

There is a JUnit mailing list, that can address more detailed questions.