You should do the following steps in order to apply parallel evaluation to your optimization algorithm:

1. Download the optimization.jar file, which is in the folder lib.
2. Add the previous file to your project libraries.
3. Substitute Solution.evaluate((Vector)pop, function); with Solution.paralelEvaluate((Vector)pop, function, numberOfThreads); in the line where the first population is being evaluated.
4. Add the line transformation.activateParalelEvaluation(numberOfThreads); after the Transformation class have been defined, for example: Transformation transformation = new HAEA(haeaOperators, grow, selection);.

Finally, if you did these four steps, your algorithm ought to be evaliating the fitness function in parallel form.