Is Java assert broken?

Question

While poking around the questions, I recently discovered the assert keyword in Java. At first, I was excited. Something useful I didn\'t already know! A more

Answer 1

Use an assert if you're willing to pay $1 to your end-user whenever the assertion fails.

An assertion failure should be an indication of a design error in the program.

An assertion states that I have engineered the program in such a way that I know and guarantee that the specified predicate always holds.

An assertion is useful to readers of my code, since they see that (1) I'm willing to set some money on that property; and (2) in previous executions and test cases the property did hold indeed.

My bet assumes that the client of my code sticks to the rules, and adheres to the contract he and I agreed upon. This contract can be tolerant (all input values allowed and checked for validity) or demanding (client and I agreed that he'll never supply certain input values [described as preconditions], and that he doesn't want me to check for these values over and over again). If the client sticks to the rules, and my assertions nevertheless fail, the client is entitled to some compensation.