  COTS-based development is a component reuse approach promising to reduce
costs and risks, and ensure higher quality. The growing availability of COTS
components on the Web has concretized the possibility of achieving these
objectives. In this multitude, a recurrent problem is the identification of the
COTS components that best satisfy the user requirements. Finding an adequate
COTS component implies searching among heterogeneous descriptions of the
components within a broad search space. Thus, the use of search engines is
required to make more efficient the COTS components identification. In this
paper, we investigate, theoretically and empirically, the COTS component search
performance of eight software component search engines, nine semantic search
engines and a conventional search engine (Google). Our empirical evaluation is
conducted with respect to precision and normalized recall. We defined ten
queries for the assessed search engines. These queries were carefully selected
to evaluate the capability of each search engine for handling COTS component
identification.
