Plasma PIC simulations model the interactions of charged particles with the surrounding fields. It has been recognized as one of the grand challenge problems facing the high-performance computing community due to its huge computational requirements. Recently, with the explosive development of Internet, Java is receiving increasing attention and is thought as a potential candidate for high-performance computing. In this paper, we present our approach to developing 2- and 3-dimensional parallel PIC simulation in Java. We also report the performance for both versions on the Sun E6500 and a Linux cluster, and the performance of their corresponding Fortran versions is compared.