中文摘要：

E-mail： {haod}@sei.pku.edu.cn; Dan Hao is a postdoctoral researcher in the School of Electronics Engineering and Computer Science at Peking University. She is a member of CCF and ACM. She received the Ph.D. degree from School of Electronics Engineering and Computer Science, Peking University in 2008. Her current research interests include software testing, debugging,and program comprehension. E-mail： {zhanglu}@sei.pku.edu.cn; Lu Zhang is an associate professor in the School of Electronics Engineering and Computer Science at Peking University. He is a member of ACM and a senior member of CCF. He received the B.S. and the Ph.D. degrees in computer science both from Peking University. He was a postdoctoral researcher with the Department of Computer Sci-ence, the University of Liverpool in April 2001-January 2003. His current research interests include program comprehension, reverse engineering, component-based software development, software modeling, and software testing. E-mail： xie@csc.ncsu.edu Tao Xie is an assistant professor in the Department of Computer Science of the College of Engineering at North Carolina State University. He received his Ph.D. degree in computer science from the University of Washington in 2005. Before that, he received an M.S. degree in computer science from the University of Washington in 2002 and an M.S. degree in computer science from Peking University in 2000. His research interests are in software engineering, with an emphasis on improving software dependability and productivity. Corresponding Author E-mail： { meih}@sei.pku.edu.cn; Hong Mei is a professor at the School of Electronics Engineering and Computer Science, Peking University and the director of Special Interest Group of Software Engineering of CCF. He received his Ph.D. degree in computer science from Shanghai Jinotong University in 1992. His current research interests include software engineering and software engi-neering environment, software reuse and software compo- nent technology, distributed object techn