How to avoid java.util.ConcurrentModificationException when iterating through and removing elements from an ArrayList

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I have an ArrayList that I want to iterate over. While iterating over it I have to remove elements at the same time. Obviously this throws a java.util.ConcurrentModificationException.

What is the best practice to handle this problem? Should I clone the list first?

I remove the elements not in the loop itself but another part of the code.

My code looks like this:

public class Test() {
    private ArrayList<A> abc = new ArrayList<A>();

    public void doStuff() {
        for (A a : abc) 
        a.doSomething();
    }

    public void removeA(A a) {
        abc.remove(a);
    }
}

a.doSomething might call Test.removeA();

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