001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.functor;
018
019/**
020 * A functor that takes two arguments and returns a value.
021 * <p>
022 * Implementors are encouraged but not required to make their functors
023 * {@link java.io.Serializable Serializable}.
024 * </p>
025 * @param <L> the left argument type.
026 * @param <R> the right argument type.
027 * @param <T> the returned value type.
028 * @since 1.0
029 * @version $Revision: 1438784 $ $Date: 2013-01-26 01:09:13 +0100 (Sa, 26 Jan 2013) $
030 */
031public interface BinaryFunction<L, R, T> extends BinaryFunctor<L, R> {
032    /**
033     * Evaluate this function.
034     *
035     * @param left the L element of the ordered pair of arguments
036     * @param right the R element of the ordered pair of arguments
037     * @return the T result of this function for the given arguments
038     */
039    T evaluate(L left, R right);
040}