基于语法和语义结合的源代码精确搜索方法

针对在编写软件、复用源代码的过程中仅依靠关键词无法精准搜索到适用源代码的问题，提出一种将语法和语义结合的源代码精准搜索方法。首先依据源代码语法语义的客观和唯一性，增加语法结构和"输入/输出"语义作为用户录入请求的一部分，并规范了具体的请求格式；然后在此基础上分别设计源代码语法匹配算法、"输入/输出"语义匹配算法、关键词兼容匹配，以及源代码搜索结果可信度计算算法；最后综合上述算法实现对源代码的精准搜索。测试结果表明：与单纯的关键词搜索相比，提出的方法对搜索的平均排序倒数（MRR）有超过62%的提升，有助于实现源代码的精准搜索。

Accurate search method for source code by combining syntactic and semantic queries

In the process of programming and source code reuse, since simple keyword-based code search often leads to inaccurate results, an accurate search method for source code was proposed. Firstly, according to the objectivity and uniqueness of syntax and semantics, the syntactic structure and semantics of I/O of a function in source code were considered as part of a query. Such query should be submitted following a regularized format. Secondly, the syntactic structure, semantics of I/O, keyword-compatible match algorithms along with the reliability calculation algorithm were designed. Finally, the accurate search method by combining syntactic and semantic queries was realized by using the above algorithms. The test result shows that the proposed method can improve Mean Reciprocal Rank (MRR) by more than 62% compared with the common keyword-based search method, and it is effective in improving the accuracy of source code search.