Assert a good practice or not?

Question

Is it a good practice to use Assert for function parameters to enforce their validity. I was going through the source code of Spring Framework and I noticed that they use

Answer 1

Based on Sun's guide on assertions, you should not use assertions for argument checking in public methods.

Argument checking is typically part of the published specifications (or contract) of a method, and these specifications must be obeyed whether assertions are enabled or disabled.