1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18 package org.apache.commons.io.function;
19
20 import java.io.IOException;
21 import java.util.function.BiFunction;
22 import java.util.stream.Stream;
23 import java.util.stream.StreamSupport;
24
25 import org.apache.commons.io.IOExceptionList;
26 import org.apache.commons.io.IOIndexedException;
27
28 /**
29 * Keep this code package-private for now.
30 */
31 final class IOStreams {
32
33 static final Object NONE = new Object();
34
35 static <T> void forAll(final Stream<T> stream, final IOConsumer<T> action) throws IOExceptionList {
36 forAll(stream, action, (i, e) -> e);
37 }
38
39 @SuppressWarnings("resource") // adapt()
40 static <T> void forAll(final Stream<T> stream, final IOConsumer<T> action, final BiFunction<Integer, IOException, IOException> exSupplier)
41 throws IOExceptionList {
42 IOStream.adapt(stream).forAll(action, IOIndexedException::new);
43 }
44
45 @SuppressWarnings("unused") // IOStreams.rethrow() throws
46 static <T> void forEach(final Stream<T> stream, final IOConsumer<T> action) throws IOException {
47 final IOConsumer<T> actualAction = toIOConsumer(action);
48 of(stream).forEach(e -> Erase.accept(actualAction, e));
49 }
50
51 /**
52 * Null-safe version of {@link StreamSupport#stream(java.util.Spliterator, boolean)}.
53 *
54 * Copied from Apache Commons Lang.
55 *
56 * @param <T> the type of stream elements.
57 * @param values the elements of the new stream, may be {@code null}.
58 * @return the new stream on {@code values} or {@link Stream#empty()}.
59 */
60 static <T> Stream<T> of(final Iterable<T> values) {
61 return values == null ? Stream.empty() : StreamSupport.stream(values.spliterator(), false);
62 }
63
64 static <T> Stream<T> of(final Stream<T> stream) {
65 return stream == null ? Stream.empty() : stream;
66 }
67
68 /**
69 * Null-safe version of {@link Stream#of(Object[])}.
70 *
71 * Copied from Apache Commons Lang.
72 *
73 * @param <T> the type of stream elements.
74 * @param values the elements of the new stream, may be {@code null}.
75 * @return the new stream on {@code values} or {@link Stream#empty()}.
76 */
77 @SafeVarargs // Creating a stream from an array is safe
78 static <T> Stream<T> of(final T... values) {
79 return values == null ? Stream.empty() : Stream.of(values);
80 }
81
82 static <T> IOConsumer<T> toIOConsumer(final IOConsumer<T> action) {
83 return action != null ? action : IOConsumer.noop();
84 }
85
86 private IOStreams() {
87 // no instances
88 }
89 }