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.juneau.internal;
018
019import java.util.*;
020import java.util.function.*;
021
022/**
023 * A function that takes in 2 arguments.
024 *
025 * <h5 class='section'>See Also:</h5><ul>
026 * </ul>
027 *
028 * @param <A> The first argument.
029 * @param <B> The second argument.
030 * @param <R> The return type.
031 */
032@SuppressWarnings("javadoc")
033@FunctionalInterface
034public interface Function2<A,B,R> {
035
036   R apply(A a, B b);
037
038   default <V> Function2<A, B, V> andThen(Function<? super R, ? extends V> after) {
039      Objects.requireNonNull(after);
040      return (A a, B b) -> after.apply(apply(a, b));
041   }
042}