The main objective of this work is to highlight the advantages of coupling Java FDTD implementation with the mobile-agent computing paradigm, and to promote this approach as a flexible and valuable tool for the distributed solution of complex and large-scale problems. Therefore, we present key issues related to the distributed implementation of a finite-difference time-domain (FDTD) code using Java mobile agents. The Java object-oriented FDTD code is described, and special agent communication and synchronization aspects related to FDTD are presented in detail.