Lecture Notes in Computer Science 3472

356 Kirsten Berkenkötter and Raimund Kirner
model-based test case generation in Section 13.3. Different modeling techniques
like timed process algebras and timed automata are discussed for real-time and
hybrid systems as well as their application in test case generation. After that,
evolutionary testing is introduced as a method for improving generated test
suites with respect to testing timing constraints in Section 13.4. We conclude
with a discussion of the presented techniques in Section 13.5.
13.2 Test Automation
Testing is one of the most time consuming parts of the software development
process. Hence, a high degree of automation is needed. The general structure
for a test automation system is the same for untimed, timed, and hybrid systems.
In contrast, the internals of the different parts of a test automation system differ,
as the specific characteristics of timed and hybrid systems must be considered.
13.2.1 Overview
First, we have to introduce some testing terminology. Testing itself means the
execution of the system to be tested which we call system under test (SUT).
The SUT is fed input data while the output data is monitored for checking its
correctness.
A test case is a set of test inputs, execution conditions, and expected results.
This does not mean that the test case necessarily gives explicit input data, it
may also specify rules for generating test data. The set of test cases for a SUT
is called test suite. Thetest procedure gives detailed information about the
set-up and execution of test cases and the evaluation of the test results. If only
the interfaces of the SUT are accessible, a test is called black-box test. In
contrast, if also internal states can be observed and influenced, a test is called
white-box test.
As stated in Peleska et al. [PAD + 98], a test automation system consists of
several logical building blocks as depicted in Figure 13.1:
• Model The test model represents the required functionality of the SUT.
More precisely, it abstracts the functionality to a sensible size to allow the
generation of a test suite with manageable size. Different representations can
be chosen, e.g. automata or process algebra.
• Test Generation The test generator uses the model for deriving test
cases. In addition, more specific test case specifications that describe
a test case or a set of test cases can be used for this purpose. The test
generator is responsible for achieving a manageable number of test cases out
of the infinitely many possible ones. Therefore it plays an important role in
the test automation system.
• Test Monitoring The execution of test cases must be monitored to keep
track of inputs and outputs. This is done by the test monitor. Ontheone
hand, this is needed for documentation purposes. On the other hand, results