ToolforJavaProgram.PDF

1 28 (2011 ) ModiChecker : Accessibility Excessiveness Analysis Tool for Java Program Dotri Quoc Kazuo Kobori Norihiro Yoshida Yoshiki Higo Katsuro Inoue In object-oriented programs, access modifiers are used to control the accessibility of fields and methods from other ob- jects. Choosing appropriate access modifiers is one of the key factors for highly secure and easily maintainable programming. In this paper, we propose a novel analysis method named Accessibility Excessiveness (AE) for each field and method in Java program, which is discrepancy between the access modifier declaration and its real usage. We have developed an AE an- alyzer - ModiChecker which analyzes each field or method of the input Java programs, and reports the excessiveness. We have applied ModiChecker to various Java programs, including several OSS, and have found that this tool is very useful to detect fields and methods with the excessive access modifiers. indiscriminately. 1 Introduction For example, Figure 1 is a case of bad access modifier To realize good encapsulation in Java programs, we setting. Suppose that we have 2 methods: Method A and have to choose appropriate access modifiers of methods Method B in class X . Method A keeps an initialization and fields in a class, which may be possibly accessed by process for Method B . It means Method A must be called other objects. However, inexperienced developers tend before Method B is called. Otherwise, Method B can not to set all of the access modifiers or as work properly. In this case, Method B should be always called via