Tutorial by Examples

Classes implementing Iterable<> interface can be used in for loops. This is actually only syntactic sugar for getting an iterator from the object and using it to get all elements sequentially; it makes code clearer, faster to write end less error-prone. public class UsingIterable { pub...

While using the foreach loop (or "extended for loop") is simple, it's sometimes beneficial to use the iterator directly. For example, if you want to output a bunch of comma-separated values, but don't want the last item to have a comma: List<String> yourData = //... Iterator<Str...

To create your own Iterable as with any interface you just implement the abstract methods in the interface. For Iterable there is only one which is called iterator(). But its return type Iterator is itself an interface with three abstract methods. You can return an iterator associated with some coll...

The Iterator.remove() method is an optional method that removes the element returned by the previous call to Iterator.next(). For example, the following code populates a list of strings and then removes all of the empty strings. List<String> names = new ArrayList<>(); names.add("...