Abstract: In view of the existing difficulties and problems associated with the practical implementation of the ray-tracing based on wavefront construction, we present a Java implementation. In comparison with the conventional Fortran implementation, the Java implementation can avoid the problems caused by data point insertion and data point repositioning when mapping from an irregular grid to a regular one. As a result, the data point can be inserted at any time during computation，without needing to treat the data point repositioning problem. Since no implementation details have been published in the literature, we first review the basic equations, the numerical schemes, and the algorithm used for realizing the wavefront construction. After that, we shortly discuss the design of Java classes and Java functions. Our experience shows that using Java can both reduce the programming effort and provide a better basis for the future development cross different platforms.

Key words: ray, ray traveltime, wavefront, wavefront construction, Java