Java tutorial
//package com.java2s; /* * Copyright (C) 2009 The Guava Authors * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import java.util.Collections; import java.util.Iterator; public class Main { static <T> Iterator<T> cycle(final Iterable<T> iterable) { return new Iterator<T>() { Iterator<T> iterator = Collections.<T>emptySet().iterator(); @Override public boolean hasNext() { return true; } @Override public T next() { if (!iterator.hasNext()) { iterator = iterable.iterator(); } return iterator.next(); } @Override public void remove() { throw new UnsupportedOperationException(); } }; } }