Bug Patterns in Java presents a methodology for diagnosing and
debugging computer programs. The act of debugging will be presented
as an ideal application of the scientific method. Skill in this area
is entirely independent of other programming skills, such as
designing for extensibility and reuse. Nevertheless, it is seldom
taught explicitly. Eric Allen lays out a theory of debugging, and how
it relates to the rest of the development cycle. In particular, he
stresses the critical role of unit testing in effective debugging. At
the same time, he argues that testing and debugging, while often
conflated, are properly considered to be distinct tasks. Upon laying
this groundwork, Allen then discusses various "bug patterns"
(recurring relationships between signaled errors and underlying bugs
in a program) that occur frequently in computer programs. For each
pattern, the book discusses how to identify them, how to treat them,
and how to prevent them.