Context: Code smell can make the decline of code quality. Code smell is not a bug, and also can't make system to run exceptionally. It just can make some difficulties for software developers to understand and maintain the source code of projects, and then cause unnecessary maintenance costs. Objective: We try to more accurately detect code smell. Method: We put forward our smell detection tool: DT for short. We use DT to detect eleven code smells through detecting two kinds of projects: lab project, industrial project. Result: We get good results by using our Smell Detection Tool (DT), comparing with some famous detection tools: Checkstyle, PMD, JDeodorant and iPlasma. Conclusion: Our method Smell Detection Tool (DT) can be used to detect 11 kinds of code smell, In the future, we will go on detecting more code smells that can't be detected, and then do a survey about code smell among the software developers and maintainers.

Abstract.Context: Although Code Smell can't cause problems with execution of project code, Code Smell can cause some potential problems of maintainability and understandability on the software projects. Meanwhile, as for the research of code smell, current research results pay attention to only several specific Code Smells, and then don't have a comprehensive detection on Code Smell. Objective: To investigate what the objective of Code Smell study is, and to find what kinds of code smells could the detection tools of code smell detect. Methods: According to the Guidelines of Kithenham, we carry out a mapping study about 22 code smells, searching the relevant papers till 2015. Results: Through the process of mapping study, 286 papers are finally included and then classified into our data records. Conclusion: Referring to detection tools, firstly they only take notice of several specific Code Smells, because these code smells can be easily measured in term of quantification. Secondly, experiment systems of these papers are almost lab projects and industrial open source not the industrial closed source projects. Thirdly, the size of most detected lab projects are under 30 KLOC. In the future, we will focus efforts on detection of Code Smells that can't be easily detected, what's more, we will put our studies under a comprehensive environment, using three types of project: lab project, open source industrial project and closed source industrial project.