Regression testing is a crucial quality assurance technique for evolving software projects, particularly Java projects. This paper introduces an effective Concolic-based regression testing method called NTDREG for Java projects. NTDREG utilizes the NTD testing method, a Concolic-enhanced method, to test units in the initial source code version. For the evolved version, NTDREG employs the WAVE-CIA method to identify and test only the changed and impacted units. This approach significantly reduces the time required compared to testing all units in the evolved source code version. We have implemented the NTDREG method in a tool and conducted experiments with several common open-source projects, yielding promising results. We discuss the method, its effectiveness, and its practical application potential.