Question

I have a strange problem with arraylist. I add objects to arraylist in for loop, everything is working fine except arraylist add method. It seems like my list is adding each object twice but I can’t find a reason of this.
Here is my code

private void generateCitizens()
{
    int counter = Constants.CITIZENS_NUMBER;
    Random r = new Random(Calendar.getInstance().getTimeInMillis());
    while(counter > 0)
    {
        int x = r.nextInt(Constants.TILES_IN_WIDTH) + 1;
        int y = r.nextInt(Constants.TILES_IN_HEIGHT) + 1;

        if(map.collisionTable[y][x] == 2)
        {
            Citizen c = new Citizen(x, y, citizenTexture.deepCopy(), map);
            citizensList.add(c);
            Log.i("Citizens count", String.valueOf(citizensList.size()));
            scene.attachChild(c);
            counter--;
        }
    }

    for(int i = 0; i<citizensList.size(); i++)
    {
        Log.i("Citizen - ", citizensList.get(i).toString());
    }
}

Constants.CITIZENS_NUMBER is 15 in this case and this is what I got in logs

05-10 15:13:36.801: I/Citizens count(3237): 2
05-10 15:13:36.801: I/Citizens count(3237): 4
05-10 15:13:36.801: I/Citizens count(3237): 6
05-10 15:13:36.801: I/Citizens count(3237): 8
05-10 15:13:36.801: I/Citizens count(3237): 10
05-10 15:13:36.811: I/Citizens count(3237): 12
05-10 15:13:36.811: I/Citizens count(3237): 14
05-10 15:13:36.811: I/Citizens count(3237): 16
05-10 15:13:36.811: I/Citizens count(3237): 18
05-10 15:13:36.821: I/Citizens count(3237): 20
05-10 15:13:36.821: I/Citizens count(3237): 22
05-10 15:13:36.821: I/Citizens count(3237): 24
05-10 15:13:36.821: I/Citizens count(3237): 26
05-10 15:13:36.831: I/Citizens count(3237): 28
05-10 15:13:36.831: I/Citizens count(3237): 30
05-10 15:13:36.831: I/Citizen -(3237): com.lpp.towndefence.Citizen@40535d40
05-10 15:13:36.831: I/Citizen -(3237): com.lpp.towndefence.Citizen@40535d40
05-10 15:13:36.831: I/Citizen -(3237): com.lpp.towndefence.Citizen@40537318
05-10 15:13:36.831: I/Citizen -(3237): com.lpp.towndefence.Citizen@40537318
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@40514688
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@40514688
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@40799fe8
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@40799fe8
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@4079c308
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@4079c308
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@4079abd8
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@4079abd8
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@4079b4a0
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@4079b4a0
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@407ba160
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@407ba160
05-10 15:13:36.841: I/Citizen -(3237): com.lpp.towndefence.Citizen@407ba230
05-10 15:13:36.851: I/Citizen -(3237): com.lpp.towndefence.Citizen@407ba230
05-10 15:13:36.851: I/Citizen -(3237): com.lpp.towndefence.Citizen@407ba300
05-10 15:13:36.861: I/Citizen -(3237): com.lpp.towndefence.Citizen@407ba300
05-10 15:13:36.861: I/Citizen -(3237): com.lpp.towndefence.Citizen@407ba3d0
05-10 15:13:36.861: I/Citizen -(3237): com.lpp.towndefence.Citizen@407ba3d0
05-10 15:13:36.861: I/Citizen -(3237): com.lpp.towndefence.Citizen@407ba4a0
05-10 15:13:36.861: I/Citizen -(3237): com.lpp.towndefence.Citizen@407ba4a0
05-10 15:13:36.861: I/Citizen -(3237): com.lpp.towndefence.Citizen@407bac18
05-10 15:13:36.861: I/Citizen -(3237): com.lpp.towndefence.Citizen@407bac18
05-10 15:13:36.871: I/Citizen -(3237): com.lpp.towndefence.Citizen@407bb3f0
05-10 15:13:36.871: I/Citizen -(3237): com.lpp.towndefence.Citizen@407bb3f0
05-10 15:13:36.871: I/Citizen -(3237): com.lpp.towndefence.Citizen@407bbc80
05-10 15:13:36.871: I/Citizen -(3237): com.lpp.towndefence.Citizen@407bbc80

Answer 1

Did you subclass the List class ?

May new Citizen add itself to the list ? Or the attachChild method on scene ?