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.FileSystemException;
21 import org.apache.commons.vfs2.FileType;
22
23 /**
24 * Implementation for layered file systems.
25 * <p>
26 * Additionally encodes the '!' character.
27 * </p>
28 */
29 public class LayeredFileNameParser extends AbstractFileNameParser {
30
31 private static final LayeredFileNameParser INSTANCE = new LayeredFileNameParser();
32
33 /**
34 * Gets the singleton instance.
35 *
36 * @return the singleton instance.
37 */
38 public static LayeredFileNameParser getInstance() {
39 return INSTANCE;
40 }
41
42 /**
43 * Constructs a new instance.
44 */
45 public LayeredFileNameParser() {
46 // empty
47 }
48
49 /**
50 * Determines if a character should be encoded.
51 *
52 * @param ch The character to check.
53 * @return true if the character should be encoded.
54 */
55 @Override
56 public boolean encodeCharacter(final char ch) {
57 return super.encodeCharacter(ch) || ch == LayeredFileName.LAYER_SEPARATOR;
58 }
59
60 /**
61 * Pops the root prefix off a URI, which has had the scheme removed.
62 *
63 * @param uri string builder which gets modified.
64 * @return the extracted root name.
65 */
66 protected String extractRootName(final StringBuilder uri) {
67 // Looking for <name>!<abspath> (staring at the end)
68 final int maxlen = uri.length();
69 int pos = maxlen - 1;
70 while (pos > 0 && uri.charAt(pos) != LayeredFileName.LAYER_SEPARATOR) {
71 pos--;
72 }
73
74 if (pos == 0 && uri.charAt(pos) != LayeredFileName.LAYER_SEPARATOR) {
75 // not ! found, so take the whole path a root
76 // e.g. zip:/my/zip/file.zip
77 pos = maxlen;
78 }
79
80 // Extract the name
81 final String prefix = uri.substring(0, pos);
82 if (pos < maxlen) {
83 uri.delete(0, pos + 1);
84 } else {
85 uri.setLength(0);
86 }
87
88 return prefix;
89 }
90
91 /**
92 * Parses the base and name into a FileName.
93 *
94 * @param context The component context.
95 * @param baseFileName The base FileName.
96 * @param fileName name The target file name.
97 * @return The constructed FileName.
98 * @throws FileSystemException if an error occurs.
99 */
100 @Override
101 public FileName parseUri(final VfsComponentContext context, final FileName baseFileName, final String fileName)
102 throws FileSystemException {
103 final StringBuilder name = new StringBuilder();
104
105 // Extract the scheme
106 final String scheme = UriParser.extractScheme(context.getFileSystemManager().getSchemes(), fileName, name);
107
108 // Extract the Layered file URI
109 final String rootUriName = extractRootName(name);
110 FileName rootUri = null;
111 if (rootUriName != null) {
112 rootUri = context.parseURI(rootUriName);
113 }
114
115 // Decode and normalise the path
116 UriParser.canonicalizePath(name, 0, name.length(), this);
117 UriParser.fixSeparators(name);
118 final FileType fileType = UriParser.normalisePath(name);
119 final String path = name.toString();
120
121 return new LayeredFileName(scheme, rootUri, path, fileType);
122 }
123
124 }