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.commons.function; 018 019import static org.apache.juneau.commons.utils.Shorts.*; 020 021 022/** 023 * A functional interface representing an operation that accepts four arguments and returns no result. 024 * 025 * <p> 026 * This interface extends the standard Java {@link java.util.function.Consumer} pattern to support 027 * four-argument consumers. It's useful when you need to pass operations with four parameters to methods 028 * that expect functional interfaces, such as in iteration, builders, or callback patterns. 029 * 030 * <h5 class='section'>Features:</h5> 031 * <ul class='spaced-list'> 032 * <li>Functional interface - can be used with lambda expressions and method references 033 * <li>Composition support - provides {@link #andThen(Consumer4)} for operation chaining 034 * <li>Side-effect operations - designed for operations that perform side effects rather than return values 035 * </ul> 036 * 037 * <h5 class='section'>Use Cases:</h5> 038 * <ul class='spaced-list'> 039 * <li>Four-argument operations in iteration patterns 040 * <li>Builder methods that accept four-parameter operations 041 * <li>Callback patterns with four parameters 042 * <li>Event handlers that process four values 043 * </ul> 044 * 045 * <h5 class='section'>Usage:</h5> 046 * <p class='bjava'> 047 * <jc>// Lambda expression</jc> 048 * Consumer4<String,Integer,Boolean,Double> <jv>printer</jv> = (<jv>name</jv>, <jv>age</jv>, <jv>active</jv>, <jv>score</jv>) -> 049 * System.<jsf>out</jsf>.println(<jv>name</jv> + <js>": age="</js> + <jv>age</jv> + <js>", active="</js> + <jv>active</jv> + <js>", score="</js> + <jv>score</jv>); 050 * <jv>printer</jv>.apply(<js>"Alice"</js>, 30, <jk>true</jk>, 95.5); <jc>// Prints "Alice: age=30, active=true, score=95.5"</jc> 051 * 052 * <jc>// Operation composition</jc> 053 * Consumer4<String,Integer,Boolean,Double> <jv>validate</jv> = (<jv>s</jv>, <jv>i</jv>, <jv>b</jv>, <jv>d</jv>) -> { 054 * <jk>if</jk> (<jv>i</jv> < 0 || <jv>d</jv> < 0) <jk>throw new</jk> IllegalArgumentException(); 055 * }; 056 * Consumer4<String,Integer,Boolean,Double> <jv>process</jv> = (<jv>s</jv>, <jv>i</jv>, <jv>b</jv>, <jv>d</jv>) -> <jsm>process</jsm>(<jv>s</jv>, <jv>i</jv>, <jv>b</jv>, <jv>d</jv>); 057 * Consumer4<String,Integer,Boolean,Double> <jv>validateAndProcess</jv> = <jv>validate</jv>.andThen(<jv>process</jv>); 058 * <jv>validateAndProcess</jv>.apply(<js>"data"</js>, 42, <jk>true</jk>, 10.5); <jc>// Validates then processes</jc> 059 * </p> 060 * 061 * <h5 class='section'>See Also:</h5><ul> 062 * <li class='jc'>{@link Consumer2} - Two-argument consumer 063 * <li class='jc'>{@link Consumer3} - Three-argument consumer 064 * <li class='jc'>{@link Consumer5} - Five-argument consumer 065 * <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/JuneauCommons">juneau-commons</a> 066 * </ul> 067 * 068 * @param <A> The type of the first argument to the operation. 069 * @param <B> The type of the second argument to the operation. 070 * @param <C> The type of the third argument to the operation. 071 * @param <D> The type of the fourth argument to the operation. 072 */ 073@FunctionalInterface 074@SuppressWarnings({ 075 "java:S1192" // Duplicated literals (argument/property names) read more clearly inline than as constants 076}) 077public interface Consumer4<A,B,C,D> { 078 079 /** 080 * Returns a composed {@link Consumer4} that performs, in sequence, this operation followed by the {@code after} operation. 081 * 082 * <p> 083 * This method enables operation composition, allowing you to chain multiple operations together. 084 * If performing either operation throws an exception, it is relayed to the caller of the composed operation. 085 * If performing this operation throws an exception, the {@code after} operation will not be performed. 086 * 087 * <h5 class='section'>Example:</h5> 088 * <p class='bjava'> 089 * Consumer4<String,Integer,Boolean,Double> <jv>log</jv> = (<jv>s</jv>, <jv>i</jv>, <jv>b</jv>, <jv>d</jv>) -> <jsm>logger</jsm>.info(<jv>s</jv> + <js>": "</js> + <jv>i</jv> + <js>", "</js> + <jv>b</jv> + <js>", "</js> + <jv>d</jv>); 090 * Consumer4<String,Integer,Boolean,Double> <jv>store</jv> = (<jv>s</jv>, <jv>i</jv>, <jv>b</jv>, <jv>d</jv>) -> <jv>cache</jv>.put(<jv>s</jv>, <jv>i</jv>, <jv>b</jv>, <jv>d</jv>); 091 * Consumer4<String,Integer,Boolean,Double> <jv>logAndStore</jv> = <jv>log</jv>.andThen(<jv>store</jv>); 092 * <jv>logAndStore</jv>.apply(<js>"data"</js>, 100, <jk>true</jk>, 50.0); <jc>// Logs and stores</jc> 093 * </p> 094 * 095 * @param after The operation to perform after this operation. Must not be <jk>null</jk>. 096 * @return A composed {@link Consumer4} that performs in sequence this operation followed by the {@code after} operation. 097 * @throws NullPointerException if {@code after} is <jk>null</jk>. 098 */ 099 default Consumer4<A,B,C,D> andThen(Consumer4<? super A,? super B,? super C,? super D> after) { 100 reqnn("after", after); 101 return (A a, B b, C c, D d) -> { 102 apply(a, b, c, d); 103 after.apply(a, b, c, d); 104 }; 105 } 106 107 /** 108 * Performs this operation on the given arguments. 109 * 110 * <h5 class='section'>Example:</h5> 111 * <p class='bjava'> 112 * Consumer4<String,Integer,Boolean,Double> <jv>handler</jv> = (<jv>key</jv>, <jv>value</jv>, <jv>flag</jv>, <jv>weight</jv>) -> { 113 * <jv>map</jv>.put(<jv>key</jv>, <jv>value</jv>); 114 * <jk>if</jk> (<jv>flag</jv>) <jv>cache</jv>.invalidate(<jv>key</jv>); 115 * <jv>stats</jv>.record(<jv>weight</jv>); 116 * }; 117 * <jv>handler</jv>.apply(<js>"user"</js>, 12345, <jk>true</jk>, 1.5); 118 * </p> 119 * 120 * @param a The first operation argument. 121 * @param b The second operation argument. 122 * @param c The third operation argument. 123 * @param d The fourth operation argument. 124 */ 125 void apply(A a, B b, C c, D d); 126}