# Ontology-Based Regression Testing: A Systematic Literature Review
## 2 Literature Review  
This section presents an overview of the existing literature on software testing regarding ontologies. In a recently published study, [PERSON] et al. [17] focused on the integration testing product lines. They claimed that the cost of integration testing was a real challenge that required the attention of researchers. They proposed a 'feature model' (FM) to support the \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Sr. No**} & \multirow{2}{*}{**Research Focus**} & **Ontology-Based** & **Number of Scholarly** & \multirow{2}{*}{**Reference**} \\  & & **Regression Testing** & **Studies** & \\ \hline
1. & Regression Testing & x & 159 & [9] \\ \hline
2. & Regression test case & x & 65 & [10] \\  & prioritization & x & 120 & [11] \\ \hline
3. & Test case prioritization & x & 120 & [12] \\ \hline
4. & Regression testing of web & \(\surd\) & 30 & [12] \\  & services & x & 47 & [3] \\ \hline
5. & Regression test case prioritization & x & 69 & [13] \\ \hline
6. & Test Case prioritization of & x & 90 & [14] \\ \hline
7. & Testing of semantic web & \(\surd\) & 43 & [15] \\ \hline
8. & Agent-based test generation & x & 115 & [16] \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Existing SLRs on regression testing. PINE method to examine integration testing costs. They reused the domain engineering artifacts to prioritize and execute the integration test cases. Their research work helped reduce 82% cost on integration testing and detecting 44% of integration faults. However, regression testing has been further explored in the following studies. [PERSON] [18] stated that many proposed web services TCP approaches showed limitations due to the high coverage of large-scale web services under regression testing. [PERSON] et al. [19] discussed service integration and emphasized corrective and perfect web services maintenance. The former type of maintenance is used for bug fixing, and the latter one typically involves the addition of new operations or already planned extensions. To meet users' requirements, web services evolve and need retesting based on the scalability behavior of web services. Therefore, regression testing involves the scalability factor in designing the approaches. The scalability issue of test case prioritization strategies was highly emphasized in a study [20]. Researchers in the same research suggested future research works on extensive web services regarding cost-saving. Another study [21] presented their proposed 'dynamic symbolic execution' (DSE) approach efficiently by analyzing the code. However, it has limited scalability due to path explosion issues. In the same study, researchers explicitly considered mitigating the limitation of the DSE approach. To further explore the use of ontology in testing, [PERSON] and [PERSON] [22] proposed a 'Software Testing Ontology for WS' (STOWS) approach to manage the semantics of web services, their registry and discovery. The authors pointed out the problem of integrating services from different owners. A collaborative testing approach was proposed to overcome this issue. The proposed approach used ontologies to support the wide range of testing activities. The same research proposed to use the crowdsourcing approach to add new vocabulary and update it for public information. The STOWS approach is scalable as a test broker can handle significant test problems for registered testers. However, the proposed approach did not reveal the risk factors in designing the approach. To overcome this issue, [PERSON] et al. [23] proposed a risk-based TCP by keeping in mind the existing TCP approaches, which use the execution information of test cases and the history of code changes. However, researchers in the above-mentioned study examined assigning the weights to classes regarding the complexity of semantic web services. By considering the system topology, we can design the information flow in the ontology of the system.