Question

Code looks like

public void option() {
    seeTasks = tasks.getTasks();
        for (int i = 0; i < seeTasks.size(); i++) {
            for (int b = 0; b < seeBoxes.size(); b++) {
               System.out.println("see Tasks: " + seeTasks.get(i) + 
                           " see Boxes " + seeBoxes.get(b));
            if(seeTasks.get(i) == seeBoxes.get(b)) {
                option.add(seeTasks.get(i));
            }
        }
    }
    System.out.println(option);
}

The if statement with seeTaks.get(i) wont go go through if the values of seeTasks.get(i) is lower than 150. How can this be? As seen below, 370 doesnt get included. If I change 110 to 150, it wont go through.

Output of println‘s is:

see Tasks: 50 see Boxes 50
see Tasks: 50 see Boxes 110
see Tasks: 50 see Boxes 150
see Tasks: 50 see Boxes 210
see Tasks: 50 see Boxes 270
see Tasks: 50 see Boxes 310
see Tasks: 50 see Boxes 370
see Tasks: 50 see Boxes 430
see Tasks: 110 see Boxes 50 
see Tasks: 110 see Boxes 110
see Tasks: 110 see Boxes 150
see Tasks: 110 see Boxes 210
see Tasks: 110 see Boxes 270
see Tasks: 110 see Boxes 310
see Tasks: 110 see Boxes 370
see Tasks: 110 see Boxes 430
see Tasks: 370 see Boxes 50
see Tasks: 370 see Boxes 110
see Tasks: 370 see Boxes 150
see Tasks: 370 see Boxes 210
see Tasks: 370 see Boxes 270
see Tasks: 370 see Boxes 310
see Tasks: 370 see Boxes 370
see Tasks: 370 see Boxes 430
[50, 110]

Answer 1

I suspect

seeTasks.get(i)

and

seeBoxes.get(b)

both return an Integer. Then for values below 128, the Integer cache returns the same instance, but for larger values, new instances. Use equals().