Jan Thomä wrote:

JUnit and asserts are not exactly equivalent technologies.  How can you
write a JUnit test that ensures that a particular method is never called
with a null value?  (Certainly not in any way that JUnit is typically used.)

Having code with asserts can be very helpful, as it is self documenting.
 If you see a method that takes a parameter x and you see an assert
that x is not null, you know that the caller is responsible for not
passing null values to the method.  Asserts lay out the assumptions made
by the code that follows.

Ray