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1
9 package com.vladium.util;
10
11 import java.io.BufferedReader  ;
12 import java.io.File ;
13 import java.io.FileReader ;
14 import java.io.IOException ;
15 import java.util.ArrayList ;
16 import java.util.HashSet ;
17 import java.util.LinkedList ;
18 import java.util.List ;
19 import java.util.Set ;
20 import java.util.StringTokenizer ;
21
22
26 public
27 abstract class Files
28 {
29
31
36 public static String [] readFileList (final File atfile)
37 throws IOException
38 {
39 if (atfile == null) throw new IllegalArgumentException ("null input: atfile");
40
41 List _result = null;
42
43 BufferedReader in = null;
44 try
45 {
46 in = new BufferedReader (new FileReader (atfile), 8 * 1024); _result = new LinkedList ();
48
49 for (String line; (line = in.readLine ()) != null; )
50 {
51 line = line.trim ();
52 if ((line.length () == 0) || (line.charAt (0) == '#')) continue;
53
54 _result.add (line);
55 }
56 }
57 finally
58 {
59 if (in != null) try { in.close (); } catch (Exception ignore) {}
60 }
61
62 if ((_result == null) || _result.isEmpty ())
63 return IConstants.EMPTY_STRING_ARRAY;
64 else
65 {
66 final String [] result = new String [_result.size ()];
67 _result.toArray (result);
68
69 return result;
70 }
71 }
72
73
88 public static File [] pathToFiles (final String [] path, final boolean canonical)
89 {
90 if (path == null) throw new IllegalArgumentException ("null input: path");
91 if (path.length == 0) return IConstants.EMPTY_FILE_ARRAY;
92
93 final List _result = new ArrayList (path.length);
94 final Set pathnames = new HashSet (path.length);
95
96 final String separators = ",".concat (File.pathSeparator);
97
98 for (int i = 0; i < path.length; ++ i)
99 {
100 String segment = path [i];
101 if (segment == null) throw new IllegalArgumentException ("null input: path[" + i + "]");
102
103 final StringTokenizer tokenizer = new StringTokenizer (segment, separators);
104 while (tokenizer.hasMoreTokens ())
105 {
106 String pathname = tokenizer.nextToken ();
107
108 if (canonical) pathname = canonicalizePathname (pathname);
109
110 if (pathnames.add (pathname))
111 {
112 _result.add (new File (pathname));
113 }
114 }
115 }
116
117 final File [] result = new File [_result.size ()];
118 _result.toArray (result);
119
120 return result;
121 }
122
123
127 public static String canonicalizePathname (final String pathname)
128 {
129 if (pathname == null) throw new IllegalArgumentException ("null input: pathname");
130
131 try
132 {
133 return new File (pathname).getCanonicalPath ();
134 }
135 catch (Exception e)
136 {
137 return new File (pathname).getAbsolutePath ();
138 }
139 }
140
141 public static File canonicalizeFile (final File file)
142 {
143 if (file == null) throw new IllegalArgumentException ("null input: file");
144
145 try
146 {
147 return file.getCanonicalFile ();
148 }
149 catch (Exception e)
150 {
151 return file.getAbsoluteFile ();
152 }
153 }
154
155
165 public static String getFileName (final File file)
166 {
167 if (file == null) throw new IllegalArgumentException ("null input: file");
168
169 final String name = file.getName ();
170 int lastDot = name.lastIndexOf ('.');
171 if (lastDot < 0) return name;
172
173 return name.substring (0, lastDot);
174 }
175
176
186 public static String getFileExtension (final File file)
187 {
188 if (file == null) throw new IllegalArgumentException ("null input: file");
189
190 final String name = file.getName ();
191 int lastDot = name.lastIndexOf ('.');
192 if (lastDot < 0) return "";
193
194 return name.substring (lastDot);
195 }
196
197
203 public static File newFile (final File dir, final File file)
204 {
205 if (file == null) throw new IllegalArgumentException ("null input: file");
206
207 if ((dir == null) || file.isAbsolute ()) return file;
208
209 return new File (dir, file.getPath ());
210 }
211
212
218 public static File newFile (final File dir, final String file)
219 {
220 if (file == null) throw new IllegalArgumentException ("null input: file");
221
222 final File fileFile = new File (file);
223 if ((dir == null) || fileFile.isAbsolute ()) return fileFile;
224
225 return new File (dir, file);
226 }
227
228
234 public static File newFile (final String dir, final String file)
235 {
236 if (file == null) throw new IllegalArgumentException ("null input: file");
237
238 final File fileFile = new File (file);
239 if ((dir == null) || fileFile.isAbsolute ()) return fileFile;
240
241 return new File (dir, file);
242 }
243
244
260 public static boolean renameFile (final File source, final File target, final boolean overwrite)
261 {
262 if ((source == null) || ! source.exists ())
263 throw new IllegalArgumentException ("invalid input source: [" + source + "]");
264 if (target == null)
265 throw new IllegalArgumentException ("null input: target");
266
267 final boolean targetExists;
268 if (! (targetExists = target.exists ()) || overwrite)
269 {
270 if (targetExists)
271 {
272 target.delete (); }
275 else
276 {
277 final File targetDir = target.getParentFile ();
279 if ((targetDir != null) && ! targetDir.equals (source.getParentFile ()))
280 targetDir.mkdirs (); }
282
283 return source.renameTo (target);
286 }
287
288 return false;
289 }
290
291
314 public static File createTempFile (final File parentDir, final String prefix, String extension)
315 throws IOException
316 {
317 if ((parentDir == null) || ! parentDir.exists ())
318 throw new IllegalArgumentException ("invalid parent directory: [" + parentDir + "]");
319 if ((prefix == null) || (prefix.length () < 3))
320 throw new IllegalArgumentException ("null or less than 3 chars long: " + prefix);
321
322 if (extension == null) extension = ".tmp";
323 else if (extension.charAt (0) != '.') extension = ".".concat (extension);
324
325 return File.createTempFile (prefix, extension, parentDir);
326 }
327
328
330
332
334
335 private Files () {}
337 } |
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