  Background: Custom static analysis rules, i.e., rules specific for one or
more applications, have been successfully applied to perform corrective and
preventive software maintenance. Pattern-Driven Maintenance (PDM) is a method
designed to support the creation of such rules during software maintenance.
However, as PDM was recently proposed, few maintainers have reported on its
usage. Hence, the challenges and skills needed to apply PDM properly are
unknown. Aims: In this paper, we investigate the challenges faced by
maintainers on applying PDM for creating custom static analysis rules for
defect localization. Method: We conducted an observational study on novice
maintainers creating custom static analysis rules by applying PDM. The study
was divided into three tasks: (i) identifying a defect pattern, (ii)
programming a static analysis rule to locate instances of the pattern, and
(iii) verifying the located instances. We analyzed the efficiency and
acceptance of maintainers on applying PDM and their comments on task
challenges. Results: We observed that previous knowledge on debugging, the
subject software, and related technologies influenced the performance of
maintainers as well as the time to learn the technology involved in rule
programming. Conclusions: The results strengthen our confidence that PDM can
help maintainers in producing custom static analysis rules for locating
defects. However, a proper selection and training of maintainers is needed to
apply PDM effectively. Also, using a higher level of abstraction can ease
static analysis rule programming for novice maintainers.
