When writing source code, developers often reuse existing source code or use libraries in order to effectively develop new software. We propose an approach to suggest method call statements to source code developers. In our study, we focus on method call statements in existing source code. A source code corpus is automatically constructed in advance from existing source code. The corpus stores method call statements before/after a method call statement. Appropriate method call statements are recommended to the developer from the corpus. We implement the proposed approach as an Eclipse plugin and clarify the effectiveness of the approach through evaluations. The evaluation results show that appropriate method call statements are ranked highly in the candidate list.

Code reuse is attracting much attention as a promising technique for efficient software development. However, code reuse itself requires human resources: for example, searching and opening source files including code fragments that users would like to reuse, or considering keywords in using code search systems. The present paper proposes a novel technique that hardly requires such reuse cost. In the proposed technique, what programmers have to do for obtaining reusable code is just inputting a trigger key for code reuse on their development environments. Also, this paper describes some applications on OSS with a prototype tool working on Eclipse.

In Open Source System (OSS) development, software components are often imported and reused; for this reason we might expect that files are copied in multiple projects (file clones). In this paper, we propose a file clone detection tool called FCFinder and show the analysis performed with it on the FreeBSD Ports Collection, a large OSS project collection. We found many file clones among similar or related projects, which are systematically introduced from base projects.

Collections of already developed programs are important resources for efficient development of reliable software systems. In this paper, we propose a novel graph-representation model of a software component library (repository), called component rank model. This is based on analyzing actual usage relations of the components and propagating the significance through the usage relations. Using the component rank model, we have developed a Java class retrieval system named SPARS-J and applied SPARS-J to various collections of Java files. The result shows that SPARS-J gives a higher rank to components that are used more frequently. As a result, software engineers looking for a component have a better chance of finding it quickly. SPARS-J has been used by two companies, and has produced promising results.

Collections of already developed programs are important resources for efficient development of reliable software systems. In this paper, we propose a novel method of ranking software components, called Component Rank, based on analyzing actual use relations among the components and propagating the significance through the use relations. We have developed a component-rank computation system, and applied it to various Java programs. The result is promising such that non-specific and generic components are ranked high. Using the Component Rank system as a core part, we are currently developing Software Product Archiving, analyzing, and Retrieving System named SPARS.

In our research demonstration, we show two development support systems for Java programs. One is an Aspect-oriented Dynamic Analysis and Slice calculation system named ADAS, and another is a Software Product archiving, Analyzing, and Retrieving System for Java named SPARS-J.

It is essential to manage versions of software products created during software development. There are various versioning tools actually used in these days, although most of them require the developers to issue management commands for consistent versioning. In this paper, we present a novel versioning file system Moraine, which accumulatively and automatically collects all files created or modified. Those files are versioned and stored as compressed forms. The older versions are easily retrieved from Moraine by the time-stamps or tags if required.