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.file;
19
20 import java.io.IOException;
21 import java.nio.file.FileVisitResult;
22 import java.nio.file.Path;
23 import java.nio.file.SimpleFileVisitor;
24 import java.util.Objects;
25
26 import org.apache.commons.io.build.AbstractSupplier;
27 import org.apache.commons.io.function.IOBiFunction;
28
29 /**
30 * A {@link SimpleFileVisitor} typed to a {@link Path}.
31 *
32 * @since 2.7
33 */
34 public abstract class SimplePathVisitor extends SimpleFileVisitor<Path> implements PathVisitor {
35
36 /**
37 * Abstracts builder for subclasses.
38 *
39 * @param <T> The SimplePathVisitor type.
40 * @param <B> The builder type.
41 * @since 2.19.0
42 */
43 protected abstract static class AbstractBuilder<T, B extends AbstractSupplier<T, B>> extends AbstractSupplier<T, B> {
44
45 private IOBiFunction<Path, IOException, FileVisitResult> visitFileFailedFunction;
46
47 /**
48 * Constructs a new builder for subclasses.
49 */
50 public AbstractBuilder() {
51 // empty.
52 }
53
54 IOBiFunction<Path, IOException, FileVisitResult> getVisitFileFailedFunction() {
55 return visitFileFailedFunction;
56 }
57
58 /**
59 * Sets the function to call on {@link #visitFileFailed(Path, IOException)}.
60 * <p>
61 * Defaults to {@link SimpleFileVisitor#visitFileFailed(Object, IOException)} on construction.
62 * </p>
63 *
64 * @param visitFileFailedFunction the function to call on {@link #visitFileFailed(Path, IOException)}.
65 * @return this instance.
66 */
67 public B setVisitFileFailedFunction(final IOBiFunction<Path, IOException, FileVisitResult> visitFileFailedFunction) {
68 this.visitFileFailedFunction = visitFileFailedFunction;
69 return asThis();
70 }
71
72 }
73
74 private final IOBiFunction<Path, IOException, FileVisitResult> visitFileFailedFunction;
75
76 /**
77 * Constructs a new instance.
78 */
79 protected SimplePathVisitor() {
80 this.visitFileFailedFunction = super::visitFileFailed;
81 }
82
83 /**
84 * Constructs a new instance.
85 *
86 * @param builder The builder provided by a subclass.
87 */
88 SimplePathVisitor(final AbstractBuilder<?, ?> builder) {
89 this.visitFileFailedFunction = builder.visitFileFailedFunction != null ? builder.visitFileFailedFunction : super::visitFileFailed;
90 }
91
92 /**
93 * Constructs a new instance.
94 *
95 * @param visitFileFailedFunction Called on {@link #visitFileFailed(Path, IOException)}.
96 */
97 protected SimplePathVisitor(final IOBiFunction<Path, IOException, FileVisitResult> visitFileFailedFunction) {
98 this.visitFileFailedFunction = Objects.requireNonNull(visitFileFailedFunction, "visitFileFailedFunction");
99 }
100
101 @Override
102 public FileVisitResult visitFileFailed(final Path file, final IOException exc) throws IOException {
103 return visitFileFailedFunction.apply(file, exc);
104 }
105 }