Comparative study of software clone detection techniques

Software cloning means duplication of source code. It is most basic means of software reuse. A software clone is a code fragment which is identical to another in the source code. Clones are harmful for software maintenance because it increases the complexity of system and maintenance cost. If we detect software clones it can decrease software maintenance cost. Many code clone detection techniques have been proposed for this purpose. Several studies show that about 5% to 20% of software system can contain duplicated code which is results of copying existing code fragments and around 60% of the efforts of an organization is wasted in maintaining this. The main disadvantage of code duplication is that if a bug is detected in a code fragment; all the other fragments similar to it should be checked for the possible existence of the same bug. By using different clone detection techniques, we can detect code clones which increase the efficiency of software maintenance process and thus decreases the maintenance cost.