Recovering and Analyzing Program Behaviors from Testing Traces

摘要

Recovering the behavior of a class in Object Oriented programming usually consists in the instrumentation either of the source or the compiled code by means of additional instructions which leave a trace of its execution. This work describes a set of algorithms to recover the behavior of a class with no modifying neither its code nor its execution environment. The idea is to execute a complete set of test cases against the class, in such way that each test case leaves a trace of the state changes of the instance in an XML file. The completion of the test set is measured in terms of the reached coverage. Thus, since each test case represents a fragment of the behavior of the class and the test set is complete, the whole set of traces represents the complete behavior of the class. This paper describes two algorithms for this goal: the first algorithm consists on the definition of generic states for the class under study, where each state depends on the values of some observer operations. After executing each operation in a test case, the state of the instance is asked and saved in the tracing file, which is later recovered and analyses. The result is an automata that provides a detailed description of the class behavior. The second algorithm analyses the XML trace files in order to extract a minimum set of rules that can be used to represent the behavior using logic programming.