SSJ is a free and open source Java library for stochastic simulation, developed under the direction of Pierre L`Ecuyer, in the Département d`Informatique et de Recherche Opérationnelle (DIRO), at the Université de Montréal.
SSJ provides facilities for generating uniform and nonuniform random variates, performing goodness-of-fit tests, applying quasi-Monte Carlo methods, collecting statistics, and programming discrete-event simulations with both events and processes.