Benchmark for testing addition and iteration of elements into a list vs a set

list_set_test.java

import java.util.*;
import java.util.concurrent.*;

class Main {
  public static void main(String[] args) {
      Set<Integer> s = Collections.newSetFromMap(new ConcurrentHashMap<Integer, Boolean>());
      CopyOnWriteArrayList<Integer> a = new CopyOnWriteArrayList<>();
    
      int total1 = 0;
      int total2 = 0;

      long ts = System.currentTimeMillis();
      for (Integer i = 0; i<100000; i++) {
          a.add(i);
      }
      System.out.println("Array add " + a.size() + " elements in " + Long.toString(System.currentTimeMillis() - ts) + "ms");

      ts = System.currentTimeMillis();
      for (Integer i = 0; i<100000; i++) {
          s.add(i);
      }
      System.out.println("Set add " + s.size() + " elements in " +  Long.toString(System.currentTimeMillis() - ts) + "ms");

      ts = System.currentTimeMillis();
      for (Integer i: a) {
          total1 += i;
      }
      System.out.println("Array Iter " + Long.toString(System.currentTimeMillis() - ts) + "ms");

      ts = System.currentTimeMillis();
      for (Integer i: s) {
          total2 += i;
      }
      System.out.println("Set Iter " + Long.toString(System.currentTimeMillis() - ts) + "ms" );

      System.out.println("END= Array sum total: " + total1 + "; Set sum total:" + total2 + ";");
  }
}

Array add 100000 elements in 3984ms
Set add 100000 elements in 34ms
Array Iter 12ms
Set Iter 16ms
END= Array sum total: 704982704; Set sum total:704982704;

Tested on Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz