Verification and Validation (V&V) processes play an important role in quality control. The earlier defects are detected, the less rework incurs. According to the findings from literature, most of the defects occurred during the design and coding phases. Automatic detection of these defects would alleviate the problem. This research therefore invented an automatic code reviewer to examine Java source files against the object-oriented design described in UML class diagrams. Prior to the review process, the class diagrams are converted into XML format so that the information of classes and relations could be extracted and used to generate the review checklists. The code reviewer will then follow the checklist items to verify whether all defined classes exist in the code, the class structures with encapsulated methods and parameters are correctly implemented, all relations of associated classes are valid. Finally, the summary report will then be generated to notify the results.