tokens: It is an open source Java library which is heavily used by the research community for designing and evaluating different multi - objective evolutionary algorithms such as -NSGA - II , NSGA - II , NSGA - III , generalized differential evolution ( GDE3 ) , strength pareto evolutionary algorithm 2 ( SPEA2 ) , indicator - based evolutionary algorithm ( IBEA ) , speed - constrained multi - objective particle swarm optimization ( SMPSO ) covariance matrix adaptation evolution strategy ( CMA - ES ) , multi - objective evolutionary algorithm with decomposition ( MOEA / D ) , and -MOEA .