How would I do roulette selection for a genetic algorithm in java this was the code I was given......Can someone give me some idea on how to do it with a 2d array

/** * Use the Roulettle Wheel selection * Remember that the sum of the fitness ratio is equal to 1. */ private int[][] Selection(int[][] Population, double[] fitness){

int[][] Parents=new int[2][Population[0].length]; //To do

return Parents; }