Anonymous internal class, iterable <t> and iterator <t>

package generic;import java.util.ArrayList;import java.util.Arrays;import java.util.Collection;import java.util.Iterator;public class ReversibleArrayList<T> extends ArrayList<T> {    private static final long serialVersionUID = -2293646393609696016L;        public ReversibleArrayList(Collection<T> collection){        super(collection);    }        public Iterable<T> reversed(){        return new Iterable<T>() {            @Override            public Iterator<T> iterator() {                return new Iterator<T>() {                    int idx = ReversibleArrayList.this.size() - 1;                    @Override                    public boolean hasNext() {                        return idx > -1;                    }                    @Override                    public T next() {                        return ReversibleArrayList.this.get(idx--);                    }                    @Override                    public void remove() {                        throw new UnsupportedOperationException();                                            }                                    };            }                    };    }        public static void main(String[] args) {        ReversibleArrayList<String> list = new ReversibleArrayList<String>(                Arrays.asList("To be or not to be".split(" ")));                for (String s : list) {            System.out.println(s);        }                System.out.println("----------------");                for (String s : list.reversed()) {            System.out.println(s);        }    }}

 

Anonymous internal class, iterable <t> and iterator <t>