Automatic protocol mining is a promising approach for inferring accurate and complete API protocols. However, just as
with  any  data-mining  technique,  this  approach  requires  sufficient  training  data  (object  usage  scenarios).  Existing  approaches
resolve the problem by analyzing more programs, which may cause significant runtime overhead. In this paper, we propose an
inheritance-based oversampling approach for object usage scenarios (OUSs). Our technique is based on the inheritance relation-
ship in object-oriented programs. Given an object-oriented program p, generally, the OUSs that can be collected from a run of p are
not more than the objects used during the run. With our technique, a maximum of n times more OUSs can be achieved, where n is
the average number of super-classes of all general OUSs. To investigate the effect of our technique, we implement it in our pre-
vious prototype tool, ISpecMiner, and use the tool to mine protocols from several real-world programs. Experimental results show
that our technique can collect 1.95 times more OUSs than general approaches. Additionally, accurate and complete API protocols
are more likely to be achieved. Furthermore, our technique can mine API protocols for classes never even used in programs, which
are valuable for validating software architectures, program documentation, and understanding. Although our technique will in-
troduce some runtime overhead, it is trivial and acceptable.

关键词： Object usage scenario,  API protocol mining,  Program temporal specification mining,  Oversampling