SpotWeb: Characterizing Framework API Usages Through a Code Search Engine

The essentials of modern software development (such as low cost and high efficiency) demand software developers to make intensive reuse of the existing open source frameworks or libraries (generally referred as frameworks) available on the web. However, developers often face challenges in reusing these frameworks due to several factors such as the complexity and lack of proper documentation. In this paper, we propose a code-search-engine-based approach that tries to detect hotspots in a given framework; these hotspots are the APIs that are frequently reused. Hotspots can serve as starting points for developers in understanding and reusing the given framework. Our approach also detects deadspots, which are the APIs that are rarely used. Deadspots serve as caveats for developers as there can be difficulties in finding related code examples and are generally less exercised compared to hotspots. We developed a tool, called SpotWeb, for frameworks or libraries written in the Java programming language and used our tool to detect hotspots and deadspots of eight open source frameworks including JUnit, Log4j, Grappa, JGraphT, OpenJGraph, JUNG, BCEL, and Javassit.