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 4 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 <C> The third argument.
031 * @param <D> The fourth argument.
032 * @param <R> The return type.
033 */
034@SuppressWarnings("javadoc")
035@FunctionalInterface
036public interface Function4<A,B,C,D,R> {
037
038   R apply(A a, B b, C c, D d);
039
040   default <V> Function4<A, B, C, D, V> andThen(Function<? super R, ? extends V> after) {
041      Objects.requireNonNull(after);
042      return (A a, B b, C c, D d) -> after.apply(apply(a, b, c ,d));
043   }
044}