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 package org.apache.commons.vfs2.provider;
18
19 import org.apache.commons.vfs2.FileName;
20 import org.apache.commons.vfs2.FileObject;
21 import org.apache.commons.vfs2.FileSystem;
22 import org.apache.commons.vfs2.FileSystemException;
23 import org.apache.commons.vfs2.FileSystemOptions;
24
25 /**
26 * A {@link FileProvider} that handles physical files, such as the files in a local fs, or on an FTP server. An
27 * originating file system cannot be layered on top of another file system.
28 */
29 public abstract class AbstractOriginatingFileProvider extends AbstractFileProvider {
30
31 public AbstractOriginatingFileProvider() {
32 }
33
34 /**
35 * Locates a file object, by absolute URI.
36 *
37 * @param baseFileObject The base file object.
38 * @param uri The URI of the file to locate
39 * @param fileSystemOptions The FileSystem options.
40 * @return The located FileObject
41 * @throws FileSystemException if an error occurs.
42 */
43 @Override
44 public FileObjectect.html#FileObject">FileObject findFile(final FileObject baseFileObject, final String uri, final FileSystemOptions fileSystemOptions)
45 throws FileSystemException {
46 // Parse the URI
47 final FileName name;
48 try {
49 name = parseUri(baseFileObject != null ? baseFileObject.getName() : null, uri);
50 } catch (final FileSystemException exc) {
51 throw new FileSystemException("vfs.provider/invalid-absolute-uri.error", uri, exc);
52 }
53
54 // Locate the file
55 return findFile(name, fileSystemOptions);
56 }
57
58 /**
59 * Locates a file from its parsed URI.
60 *
61 * @param fileName The file name.
62 * @param fileSystemOptions FileSystem options.
63 * @return A FileObject associated with the file.
64 * @throws FileSystemException if an error occurs.
65 */
66 protected FileObject findFile(final FileName fileName, final FileSystemOptions fileSystemOptions)
67 throws FileSystemException {
68 // Check in the cache for the file system
69 final FileName rootName = getContext().getFileSystemManager().resolveName(fileName, FileName.ROOT_PATH);
70
71 final FileSystem fs = getFileSystem(rootName, fileSystemOptions);
72
73 // Locate the file
74 // return fs.resolveFile(name.getPath());
75 return fs.resolveFile(fileName);
76 }
77
78 /**
79 * Returns the FileSystem associated with the specified root.
80 *
81 * @param rootFileName The root path.
82 * @param fileSystemOptions The FileSystem options.
83 * @return The FileSystem.
84 * @throws FileSystemException if an error occurs.
85 * @since 2.0
86 */
87 protected synchronized FileSystem getFileSystem(final FileName rootFileName, final FileSystemOptions fileSystemOptions)
88 throws FileSystemException {
89 FileSystem fs = findFileSystem(rootFileName, fileSystemOptions);
90 if (fs == null) {
91 // Need to create the file system, and cache it
92 fs = doCreateFileSystem(rootFileName, fileSystemOptions);
93 addFileSystem(rootFileName, fs);
94 }
95 return fs;
96 }
97
98 /**
99 * Creates a {@link FileSystem}. If the returned FileSystem implements {@link VfsComponent}, it will be initialized.
100 *
101 * @param rootFileName The name of the root file of the file system to create.
102 * @param fileSystemOptions The FileSystem options.
103 * @return The FileSystem.
104 * @throws FileSystemException if an error occurs.
105 */
106 protected abstract FileSystem doCreateFileSystem(final FileName rootFileName, final FileSystemOptions fileSystemOptions)
107 throws FileSystemException;
108 }