Classification Tree Method

These aspects form the input and output data space of the test object.

[6] Prerequisites for applying the classification tree method (CTM) is the selection (or definition) of a system under test.

[4] Any system under test can be described by a set of classifications, holding both input and output parameters.

For the Access Method, again three classes are identified: Native Tool, Web Browser, API.

Using the graphical representation in terms of a tree, the selected aspects and their corresponding values can quickly be reviewed.

For the statistics, there are 30 possible test cases in total (2 privileges * 3 operations * 5 access methods).

In the second step, three test cases have been manually selected: The CTM introduced the following advantages[2] over the Category Partition Method[7] (CPM) by Ostrand and Balcer: The classification tree method first was intended for the design and specification of abstract test cases.

With the classification tree method for embedded systems,[8] test implementation can also be performed.

Several additional features are integrated with the method: The module and unit testing tool Tessy relies on this extension.

Lehmann and Wegener introduced Dependency Rules based on Boolean expressions with their incarnation of the CTE.

Recent enhancements to the classification tree method include the prioritized test case generation: It is possible to assign weights to the elements of the classification tree in terms of occurrence and error probability or risk.

The original version of CTE was developed at Daimler-Benz Industrial Research[6][16] facilities in Berlin.

The CTE 2 was licensed to Razorcat in 1997 and is part of the TESSY unit test tool.

New developments included: In 2014, Berner&Mattner started releasing its classification tree editor under the brand name TESTONA.