Black box + White box testing

PostmanPat

Could anyone tell me what these are and the difference between them??

---

PostmanPat
__/"\

Draco

A search in www.google.com for "black box testing" will bring up a bunch of links.

Baz_

But if you don't want to trawl through em, try this out for size.

White Box Testing
============================================
white box testing is performed as a test of the internal logic of a module or program, and for this reason, you must know exactly what the module is supposed to do.
There are three ways (that I know of) of doing a white box test.

The first is a statement test, which tests every statement in the module. However you must remember that in a multiple branched if statement you are only required to go through one of the branches in order for the test to have been successful.

Next there is branch testing which requires you to go through every branch of a multiple if structure, its weakness is in branches with multiple conditions, and multiple logical conditions.

The ultimate white box test is one which tests for every single possible branch and every single condition in the module, needless to say that even with an uncomplex module this is a hard if not impossible thing to ensure.

============================================
Black Box Testing
============================================
A black box test is when you know what inputs the module requires, and what the expected output for that set of inputs is.

The ultimate test set is all possible inputs that the module can accept, again this is an almost impossible task, as most most modules can take in an immense amount of inputs.

===========================================
In summary
===========================================
white box test = you know exactly what the module does ie you know the code.
black box test = you know what inputs are required, you don't know how the outputs are arrived at but you do know what outputs to expect.
===========================================

Hope that helps