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.io.function;
019
020import java.io.IOException;
021import java.io.UncheckedIOException;
022import java.util.Objects;
023import java.util.function.Consumer;
024import java.util.stream.Stream;
025
026import org.apache.commons.io.IOExceptionList;
027import org.apache.commons.io.IOIndexedException;
028
029/**
030 * Like {@link Consumer} but throws {@link IOException}.
031 *
032 * @param <T> the type of the input to the operations.
033 * @since 2.7
034 */
035@FunctionalInterface
036public interface IOConsumer<T> {
037
038    /**
039     * Consider private.
040     */
041    IOConsumer<?> NOOP_IO_CONSUMER = t -> {/* noop */};
042
043    /**
044     * Performs an action for each element of the collection gathering any exceptions.
045     *
046     * @param action The action to apply to each input element.
047     * @param iterable The input to stream.
048     * @param <T> The element type.
049     * @throws IOExceptionList if any I/O errors occur.
050     * @since 2.12.0
051     */
052    static <T> void forAll(final IOConsumer<T> action, final Iterable<T> iterable) throws IOExceptionList {
053        IOStreams.forAll(IOStreams.of(iterable), action);
054    }
055
056    /**
057     * Performs an action for each element of the collection gathering any exceptions.
058     *
059     * @param action The action to apply to each input element.
060     * @param stream The input to stream.
061     * @param <T> The element type.
062     * @throws IOExceptionList if any I/O errors occur.
063     * @since 2.12.0
064     */
065    static <T> void forAll(final IOConsumer<T> action, final Stream<T> stream) throws IOExceptionList {
066        IOStreams.forAll(stream, action, IOIndexedException::new);
067    }
068
069    /**
070     * Performs an action for each element of the array, gathering any exceptions.
071     *
072     * @param action The action to apply to each input element.
073     * @param array The input to stream.
074     * @param <T> The element type.
075     * @throws IOExceptionList if any I/O errors occur.
076     * @since 2.12.0
077     */
078    @SafeVarargs
079    static <T> void forAll(final IOConsumer<T> action, final T... array) throws IOExceptionList {
080        IOStreams.forAll(IOStreams.of(array), action);
081    }
082
083    /**
084     * Performs an action for each element of the collection, stopping at the first exception.
085     *
086     * @param <T> The element type.
087     * @param iterable The input to stream.
088     * @param action The action to apply to each input element.
089     * @throws IOException if an I/O error occurs.
090     * @since 2.12.0
091     */
092    static <T> void forEach(final Iterable<T> iterable, final IOConsumer<T> action) throws IOException {
093        IOStreams.forEach(IOStreams.of(iterable), action);
094    }
095
096    /**
097     * Performs an action for each element of the stream, stopping at the first exception.
098     *
099     * @param <T> The element type.
100     * @param stream The input to stream.
101     * @param action The action to apply to each input element.
102     * @throws IOException if an I/O error occurs.
103     * @since 2.12.0
104     */
105    static <T> void forEach(final Stream<T> stream, final IOConsumer<T> action) throws IOException {
106        IOStreams.forEach(stream, action);
107    }
108
109    /**
110     * Performs an action for each element of this array, stopping at the first exception.
111     *
112     * @param <T> The element type.
113     * @param array The input to stream.
114     * @param action The action to apply to each input element.
115     * @throws IOException if an I/O error occurs.
116     * @since 2.12.0
117     */
118    static <T> void forEach(final T[] array, final IOConsumer<T> action) throws IOException {
119        IOStreams.forEach(IOStreams.of(array), action);
120    }
121
122    /**
123     * Returns the constant no-op consumer.
124     *
125     * @param <T> Type consumer type.
126     * @return a constant no-op consumer.
127     * @since 2.9.0
128     */
129    @SuppressWarnings("unchecked")
130    static <T> IOConsumer<T> noop() {
131        return (IOConsumer<T>) NOOP_IO_CONSUMER;
132    }
133
134    /**
135     * Performs this operation on the given argument.
136     *
137     * @param t the input argument
138     * @throws IOException if an I/O error occurs.
139     */
140    void accept(T t) throws IOException;
141
142    /**
143     * Returns a composed {@link IOConsumer} that performs, in sequence, this operation followed by the {@code after}
144     * operation. If performing either operation throws an exception, it is relayed to the caller of the composed operation.
145     * If performing this operation throws an exception, the {@code after} operation will not be performed.
146     *
147     * @param after the operation to perform after this operation
148     * @return a composed {@link Consumer} that performs in sequence this operation followed by the {@code after} operation
149     * @throws NullPointerException if {@code after} is null
150     */
151    default IOConsumer<T> andThen(final IOConsumer<? super T> after) {
152        Objects.requireNonNull(after, "after");
153        return (final T t) -> {
154            accept(t);
155            after.accept(t);
156        };
157    }
158
159    /**
160     * Creates a {@link Consumer} for this instance that throws {@link UncheckedIOException} instead of {@link IOException}.
161     *
162     * @return an UncheckedIOException Consumer.
163     * @since 2.12.0
164     */
165    default Consumer<T> asConsumer() {
166        return t -> Uncheck.accept(this, t);
167    }
168
169}