中文摘要：

E-mail： {haod, zhanglu, liumh, lihe06, sjs}@sei.pku.edu.cn Dan Hao is a postdoctoral re- searcher in the School of Electronics Engineering and Computer Science at Peking University and a mem- ber of China Computer Federation （CCF）. She received the Ph.D. de- gree from the School of Electronics Engineering and Computer Science, Peking University in 2008. Her cur- rent research interests include software testing, debugging, and program comprehension. Corresponding Author Lu Zhang is an associate profes- sor in the School of Electronics En- gineering and Computer Science at Peking University and a senior mem- ber of China Computer Federation （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 Science, the University of Liverpool. His current research in- terests include program comprehension, reverse engineering, component-based software development, software modeling, and software testing. Ming-Hao Liu received the M.S. degree from the School of Electronics Engineering and Computer Science, Peking University in 2008. His cur- rent research interests include program comprehension and software testing. He Li is a graduate student in the School of Electronics Engineer- ing and Computer Science, Peking University. He received the B.S. de- gree from the School of Electron- ics Engineering and Computer Sci- ence, Peking University. His cur- rent research interests include pro- gram comprehension and reverse en- gineering. Jia-Su Sun is a professor at the School of Electronics Engineer- ing and Computer Science at Peking University and a senior member of China Computer Federation （CCF）. His research interests include pro- gramming languages, program com- prehension, reverse engineering and reengineering. He has published more than 30 papers and led many research projects of the state.