1 /* 2 * Copyright (c) 2012, 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 package java.util.function; 26 27 import java.util.Objects; 28 29 /** 30 * An operation upon input objects. The operation may modify that object or 31 * external state (other objects). 32 * 33 * <p>All block implementations are expected to: <ul> 34 * 35 * <li>When used for aggregate operations upon many elements blocks should not 36 * assume that the {@code accept} operation will be called upon elements in any 37 * specific order.</li> 38 * </ul> 39 * 40 * @param <L> the type of input objects provided to {@code accept}. 41 * @param <R> the type of input objects provided to {@code accept}. 42 */ 43 public interface BiBlock<L, R> { 44 45 /** 46 * Performs operations upon the provided object which may modify that object 47 * and/or external state. 48 * 49 * @param l an input object 50 */ 51 void accept(L l, R r); 52 53 /** 54 * Returns a Block which performs in sequence the {@code apply} methods of 55 * multiple Blocks. This Block's {@code apply} method is performed followed 56 * by the {@code apply} method of the specified Block operation. 57 * 58 * @param other an additional Block which will be chained after this Block 59 * @return a Block which performs in sequence the {@code apply} method of 60 * this Block and the {@code apply} method of the specified Block operation 61 */ 62 public default BiBlock<L, R> chain(BiBlock<? super L, ? super R> other) { 63 Objects.requireNonNull(other); 64 65 return (l, r) -> { 66 accept(l, r); 67 other.accept(l, r); 68 }; 69 } 70 }