How convert the Traveling Salesperson JS to Object-oriented Programming style Java Processing

[psamead]

Thanks for your kindly reply. This is very helpful and figuring out my mistake. The keywords are extremely useful to let me understand the topics behind. May I ask you a few more questions, if you have time to answer.

@Chrisir

int numB = floor(random(numA, index.size())); // Added numA here !!!

Is it to avoid the same number be picked here?

@Chrisir

if (random(1) < mutationRate)
      {
        int indexA = floor(random(order.size()));
        int indexB = (indexA + 1) % totalCities;
        //print("before: " ); 
        //println(order);
        swap(order, indexA, indexB);
        //print("after: " );
        //println(order);
        //println("");
      }

It seems there are difference generated even without ‘numA’ being added.

@Chrisir

(indexA + 1) % totalCities;

Is here using % to give a reverse series of number? But why + 1 ? Because the floor function is used?

Sorry for my English.
Very appreciate your time on my work befoe. Thank you again.