Question

    ArrayList<Object> list = new ArrayList<Object>();
    list.add(12);
    list.add("Hello");
    list.add(true);
    list.add('c');

    Iterator iterator = list.iterator();
    while(iterator.hasNext())
    {
        System.out.println(iterator.next().toString());
    }

When I enter this Java code in IntelliJ IDEA, the code analysis feature suggests that I replace the while loop with a for each loop since I’m iterating on a collection. Why is this?

Answer 1

This is what it wants you to use:

for (Object o : list)
{
    System.out.println(o.toString());
}

This has been in the language since Java 1.5, and is the idiomatic pattern. You need the Iterator only if you need access to the iterator’s other methods (i.e. remove()).