Code smells refer to poor design patterns or design defects that are considered to have negative impacts on software evolution and maintenance. Many researchers have been devoted into studies on these effects and correlations in recent years. Previous researches indicated that code smells might vary with the evolution of software. In normal cases, the software evolution involves addition, modification, and deletion of source files. Therefore, the understanding of the correlations between code smells and software evolution will be helpful for developers in scheduling the development process and in code refactoring. Thus, in this study, on 8 popular Java projects with 104 released versions, an extensive empirical study is conducted to investigate 13 kinds of code smells. It is found that, as the software evolves, the proportion of files that contain code smell in all files reflects different characteristics in different projects. Additionally, the files containing smells are prone to be modified while the smells are not strongly correlated with adding or deleting files. Furthermore, among all the smells studied, some certain ones have significant impact on the file changes and obvious overlap exists in these specific smelly files. These findings are beneficial for developers to achieve in-depth comprehension of code smells, which will lead to better software maintenance.