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.chain.web; 018 019import java.util.Objects; 020 021/** 022 * Represents an operation that accepts a single input argument and returns no 023 * result. Unlike most other functional interfaces, {@code Consumer} is expected 024 * to operate via side-effects. With this functional interface it is possible 025 * that an exception is thrown. 026 * 027 * <p>This is a <a href="package-summary.html">functional interface</a> 028 * whose functional method is {@link #accept(Object)}. 029 * 030 * @param <T> the type of the input to the operation 031 * @param <E> the type of the exception to the operation 032 * 033 * @since Chain 1.3 034 */ 035@FunctionalInterface 036public interface CheckedConsumer<T, E extends Throwable> { 037 038 /** 039 * Performs this operation on the given argument. 040 * 041 * @param t the input argument 042 * 043 * @throws E the possible exception 044 */ 045 void accept(T t) throws E; 046 047 /** 048 * Returns a composed {@code CheckedConsumer} that performs, in sequence, this 049 * operation followed by the {@code after} operation. If performing either 050 * operation throws an exception, it is relayed to the caller of the 051 * composed operation. If performing this operation throws an exception, 052 * the {@code after} operation will not be performed. 053 * 054 * @param after the operation to perform after this operation 055 * 056 * @return a composed {@code Consumer} that performs in sequence this 057 * operation followed by the {@code after} operation 058 * 059 * @throws NullPointerException if {@code after} is null 060 * @throws E the possible exception 061 */ 062 default CheckedConsumer<T, E> andThen(CheckedConsumer<? super T, E> after) throws E { 063 Objects.requireNonNull(after); 064 return (T t) -> { 065 accept(t); 066 after.accept(t); 067 }; 068 } 069}