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Testing Off-the-Shelf Systems vs. Custom OO Systems

publish date: 2026/06/19 10:41:44.446853 UTC

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A hospital acquires a patient records system by adapting an existing off-the-shelf information system. How does testing an adapted off-the-shelf system differ from testing software developed from scratch using an object-oriented language?

Testing focuses more on integration and configuration rather than individual component defects, since the core components were previously tested in other contexts

Off-the-shelf systems require more unit testing because all code is new

Off-the-shelf systems cannot be tested because the source code is not available

Off-the-shelf systems always pass all acceptance tests because they are already proven products

Correct Answer

Testing focuses more on integration and configuration rather than individual component defects, since the core components were previously tested in other contexts

Explanation

Testing adapted off-the-shelf systems differs because: (1) core components were tested in other contexts, so focus shifts to integration and configuration testing; (2) source code may be unavailable, limiting white-box testing; (3) defects more often arise from incorrect configuration or integration than from component-level code bugs; (4) interaction between the off-the-shelf base system and custom adaptations is a primary test concern.

Reference

Software Engineering, Ian Sommerville, 10th edition

Quizzes you can take where this question appears

Software Testing - Exercises