1 /* 2 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package java.lang; 27 28 import java.util.Iterator; 29 import java.util.Objects; 30 import java.util.function.Block; 31 32 /** 33 * Implementing this interface allows an object to be the target of 34 * the "foreach" statement. 35 * 36 * @param <T> the type of elements returned by the iterator 37 * 38 * @since 1.5 39 */ 40 public interface Iterable<T> { 41 42 /** 43 * Returns an iterator over a set of elements of type T. 44 * 45 * @return an Iterator. 46 */ 47 Iterator<T> iterator(); 48 49 /** 50 * Execute the specified Block for each element 51 * 52 * @param block The Block to which elements will be provided 53 * @throws NullPointerException if the specified block is null 54 * @since 1.8 55 */ 56 public default void forEach(Block<? super T> block) { 57 Objects.requireNonNull(block); 58 for (T t : this) { 59 block.accept(t); 60 } 61 } 62 }