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 */
017
018package org.apache.commons.lang3.function;
019
020import java.util.Objects;
021import java.util.function.Consumer;
022
023/**
024 * A functional interface like {@link Consumer} that declares a {@code Throwable}.
025 *
026 * @param <T> Consumed type 1.
027 * @param <E> Thrown exception.
028 * @since 3.11
029 */
030@FunctionalInterface
031public interface FailableConsumer<T, E extends Throwable> {
032
033    /** NOP singleton */
034    @SuppressWarnings("rawtypes")
035    FailableConsumer NOP = t -> {/* NOP */};
036
037    /**
038     * Returns The NOP singleton.
039     *
040     * @param <T> Consumed type 1.
041     * @param <E> Thrown exception.
042     * @return The NOP singleton.
043     */
044    static <T, E extends Throwable> FailableConsumer<T, E> nop() {
045        return NOP;
046    }
047
048    /**
049     * Accepts the consumer.
050     *
051     * @param object the parameter for the consumable to accept
052     * @throws E Thrown when the consumer fails.
053     */
054    void accept(T object) throws E;
055
056    /**
057     * Returns a composed {@code Consumer} like {@link Consumer#andThen(Consumer)}.
058     *
059     * @param after the operation to perform after this operation
060     * @return a composed {@code Consumer} like {@link Consumer#andThen(Consumer)}.
061     * @throws NullPointerException when {@code after} is null
062     */
063    default FailableConsumer<T, E> andThen(final FailableConsumer<? super T, E> after) {
064        Objects.requireNonNull(after);
065        return (final T t) -> {
066            accept(t);
067            after.accept(t);
068        };
069    }
070}