1.2.2 Research Motivation The laws of software evolution were introduced in the nineteen seventies by researchers Belady & Lehman who studied how the IBM's operating system 360-series evolved. One of the key messages of software evolution is that software products need to be continuously modified in order to maintain the competitive edge. Another main point is that continuous makes software structure more complex, unless effort is made to reduce this modification complexity. One way to reduce this complexity is to apply a technique called refactoring, which aims to improve the software structure without changing the software's observable behavior. Good programmers have always modified their code to improve its structure, ie, they have applied refactoring without knowing it. However, yyonly in recent years has making it more popular. been recognized as an important part of software development thus In order to identify candidate spots for refactoring Fowler and Beck (Rowler & Beck 2000 give a list of bad smells that can exist in source code. Bad smells bear close resemblance to development level AntiPatterns (Brown et al. 1998), which also describe different problems Little academic work has been done to investigate these issues, which are widely recognized in software indus So I feel there is a need for this the software structure can kind of academic research