unit testing - How to avoid multiple asserts in a JUnit test?

Question

I have a DTO which I'm populating from the request object, and the request object has many fields. I want to write a test to check if the populateDTO() method is putting values in the right places or not. If I follow the rule of one assert per test, I would have to write a large number of tests, to test each field. The other approach would be to write multiple asserts in a single test. Is it really recommended to follow one assert per test rule or can we relax in these cases. How do I approach this problem?

Answer 1

Keep them separate. A unit test is supposed to tell you which unit failed. Keeping them separate also allows you to isolate the problem quickly w/o requiring you to go through a lengthy debug cycle.