How to deal with ConcurrentModificationException

Question

I am getting the a ConcurrentModificationException from my cooldown timer. I use a thread to reduce the values every second like this:

public class CoolDownT         


        

Answer 1

You can't modify collections when using a foreach loop.

You can however iterate over the Map.entrySet() and do everything you need:

public void run() {
    for (Iterator> i = playerCooldowns.entrySet().iterator(); i.hasNext();) {
        Map.Entry entry = i.next();
        entry.setValue(entry.getValue() - 20); // update via the Map.Entry
        if (entry.getValue() <= 0) {
            i.remove(); // remove via the iterator
        }
    }
}