thesis - Faculty of Information and Communication Technologies ...
thesis - Faculty of Information and Communication Technologies ...
thesis - Faculty of Information and Communication Technologies ...
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Chapter 2. S<strong>of</strong>tware Evolution<br />
In our study <strong>of</strong> change we aim to address these gaps by focusing our<br />
effort towards developing statistical models that can help establish normal<br />
<strong>and</strong> unusual patterns <strong>of</strong> change. We also use these models to underst<strong>and</strong><br />
better how evolving s<strong>of</strong>tware systems grow, in particular, we<br />
can identify if growth is achieved by creating new abstractions, or if<br />
existing abstractions are modified <strong>and</strong> extended.<br />
2.6 Research Questions<br />
Evolution in s<strong>of</strong>tware has been a field that has been investigated over<br />
the past few decades, with a heavier emphasis on object-oriented s<strong>of</strong>tware<br />
systems over the past decade. These studies consistently establish<br />
that evolution causes growth as s<strong>of</strong>tware is adapted to meet changing<br />
user requirements. In this chapter, we presented a summary <strong>of</strong> the key<br />
studies related to our focus areas – growth <strong>and</strong> change. A common aspect<br />
across much <strong>of</strong> the previous work is that the studies have focused<br />
on a few s<strong>of</strong>tware systems, used different input data sources in their<br />
investigation, <strong>and</strong> the abstractions under study have not been consistent<br />
across these studies. Furthermore, the current underst<strong>and</strong>ing <strong>of</strong><br />
growth has been established primarily by studies <strong>of</strong> aggregate system<br />
level size <strong>and</strong> complexity growth rather than by how this growth is distributed<br />
across the various parts <strong>of</strong> the s<strong>of</strong>tware system. The focus<br />
<strong>of</strong> studies on change has been on identification <strong>of</strong> attributes that can<br />
make an entity change-prone, with a significant emphasis on changes<br />
during the construction <strong>of</strong> a release rather than post-release.<br />
In order to address the gaps identified, we framed a set <strong>of</strong> research<br />
questions related to growth <strong>and</strong> change. As indicated earlier, our intention<br />
is to study growth in terms <strong>of</strong> how it is distributed across the<br />
various classes within an object-oriented s<strong>of</strong>tware system. We investigate<br />
change as a means to better underst<strong>and</strong> growth as well as to how<br />
<strong>and</strong> where the maintenance effort is focused by the developers as they<br />
modify, add <strong>and</strong> remove classes.<br />
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