Statistical Migration of API Usages

To support code migration, we introduce JV2CS, a tool to generate asequence of C# API elements and related control units that are neededto migrate a given Java code fragment. First, we mine the mappingsbetween single APIs in Java and C#. To overcome the lexical mismatchbetween the names of Java and C# APIs, we represent an API by itsusages instead of its name. To characterize an API with its contextconsisting of surrounding APIs in its usages, we take advantage ofWord2Vec model to project the APIs of Java JDK and C# .NET intothe corresponding continuous vector spaces. The transformation matrixbetween the two vector spaces is learned from a small set of human-written pairs of mappings. We use the transformation matrix toderive other mappings, and then use the mappings to generate thecorresponding API sequence in C# via a phrase-based translation model. The video demo for JV2CS can be found athttps://www.youtube.com/watch?v=MjTfmr9AmR8&feature=youtu.be.