The Assert Statement

Introduced with Java 1.4, the assert statement helps to debug code and also troubleshoot applications after they have been deployed. You write an assert statement stating some very important condition that you believe will always be true at this point in your program. If the condition is not true, the assertion throws an Error (a Throwable thing that is not intended to be caught). You can do that already in Java. The part that is new is that assertion statements let you choose at run-time whether the assertion checking is on or off.

Two key steps in using assert

There are two key pieces to using asserts.

  • First, you sprinkle assert statements at a few critical places in your program. For example, after calculating ...

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