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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.eclipse.aether.spi.io;
20  
21  import java.io.*;
22  import java.nio.ByteBuffer;
23  import java.nio.file.Files;
24  import java.nio.file.NoSuchFileException;
25  import java.nio.file.Path;
26  
27  /**
28   * A utility component to perform file-based operations.
29   *
30   * @since 2.0.0
31   */
32  public interface PathProcessor {
33      /**
34       * Returns last modified of path in milliseconds, if exists.
35       *
36       * @param path The path, may be {@code null}.
37       * @throws UncheckedIOException If an I/O error occurs.
38       */
39      default long lastModified(Path path, long defValue) {
40          try {
41              return Files.getLastModifiedTime(path).toMillis();
42          } catch (NoSuchFileException e) {
43              return defValue;
44          } catch (IOException e) {
45              throw new UncheckedIOException(e);
46          }
47      }
48  
49      /**
50       * Returns size of file, if exists.
51       *
52       * @param path The path, may be {@code null}.
53       * @throws UncheckedIOException If an I/O error occurs.
54       */
55      default long size(Path path, long defValue) {
56          try {
57              return Files.size(path);
58          } catch (NoSuchFileException e) {
59              return defValue;
60          } catch (IOException e) {
61              throw new UncheckedIOException(e);
62          }
63      }
64  
65      /**
66       * Writes the given data to a file. UTF-8 is assumed as encoding for the data. Creates the necessary directories for
67       * the target file. In case of an error, the created directories will be left on the file system.
68       *
69       * @param target The file to write to, must not be {@code null}. This file will be overwritten.
70       * @param data The data to write, may be {@code null}.
71       * @throws IOException If an I/O error occurs.
72       */
73      void write(Path target, String data) throws IOException;
74  
75      /**
76       * Writes the given stream to a file. Creates the necessary directories for the target file. In case of an error,
77       * the created directories will be left on the file system.
78       *
79       * @param target The file to write to, must not be {@code null}. This file will be overwritten.
80       * @param source The stream to write to the file, must not be {@code null}.
81       * @throws IOException If an I/O error occurs.
82       */
83      void write(Path target, InputStream source) throws IOException;
84  
85      /**
86       * Moves the specified source file to the given target file. If the target file already exists, it is overwritten.
87       * Creates the necessary directories for the target file. In case of an error, the created directories will be left
88       * on the file system.
89       *
90       * @param source The file to move from, must not be {@code null}.
91       * @param target The file to move to, must not be {@code null}.
92       * @throws IOException If an I/O error occurs.
93       */
94      void move(Path source, Path target) throws IOException;
95  
96      /**
97       * Copies the specified source file to the given target file. Creates the necessary directories for the target file.
98       * In case of an error, the created directories will be left on the file system.
99       *
100      * @param source The file to copy from, must not be {@code null}.
101      * @param target The file to copy to, must not be {@code null}.
102      * @throws IOException If an I/O error occurs.
103      */
104     void copy(Path source, Path target) throws IOException;
105 
106     /**
107      * Copies the specified source file to the given target file. Creates the necessary directories for the target file.
108      * In case of an error, the created directories will be left on the file system.
109      *
110      * @param source The file to copy from, must not be {@code null}.
111      * @param target The file to copy to, must not be {@code null}.
112      * @param listener The listener to notify about the copy progress, may be {@code null}.
113      * @return The number of copied bytes.
114      * @throws IOException If an I/O error occurs.
115      */
116     long copy(Path source, Path target, ProgressListener listener) throws IOException;
117 
118     /**
119      * A listener object that is notified for every progress made while copying files.
120      *
121      * @see PathProcessor#copy(Path, Path, ProgressListener)
122      */
123     interface ProgressListener {
124 
125         void progressed(ByteBuffer buffer) throws IOException;
126     }
127 }