1 /*
2 * Copyright (c) 1998, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package javax.swing.filechooser;
27
28
29 import javax.swing.*;
30
31 import java.awt.Image;
32 import java.io.File;
33 import java.io.FileNotFoundException;
34 import java.io.IOException;
35 import java.text.MessageFormat;
36 import java.util.List;
37 import java.util.ArrayList;
38 import java.lang.ref.WeakReference;
39 import java.beans.PropertyChangeListener;
40 import java.beans.PropertyChangeEvent;
41 import java.security.AccessController;
42 import java.security.PrivilegedAction;
43
44 import sun.awt.shell.*;
45
46 /**
47 * FileSystemView is JFileChooser's gateway to the
48 * file system. Since the JDK1.1 File API doesn't allow
49 * access to such information as root partitions, file type
50 * information, or hidden file bits, this class is designed
51 * to intuit as much OS-specific file system information as
52 * possible.
53 *
54 * <p>
55 *
56 * Java Licensees may want to provide a different implementation of
57 * FileSystemView to better handle a given operating system.
58 *
59 * @author Jeff Dinkins
60 */
61
62 // PENDING(jeff) - need to provide a specification for
63 // how Mac/OS2/BeOS/etc file systems can modify FileSystemView
64 // to handle their particular type of file system.
65
66 public abstract class FileSystemView {
67
68 static FileSystemView windowsFileSystemView = null;
69 static FileSystemView unixFileSystemView = null;
70 //static FileSystemView macFileSystemView = null;
71 static FileSystemView genericFileSystemView = null;
72
73 private boolean useSystemExtensionHiding =
74 UIManager.getDefaults().getBoolean("FileChooser.useSystemExtensionHiding");
75
76 public static FileSystemView getFileSystemView() {
77 if(File.separatorChar == '\\') {
78 if(windowsFileSystemView == null) {
79 windowsFileSystemView = new WindowsFileSystemView();
80 }
81 return windowsFileSystemView;
82 }
83
84 if(File.separatorChar == '/') {
85 if(unixFileSystemView == null) {
86 unixFileSystemView = new UnixFileSystemView();
87 }
88 return unixFileSystemView;
89 }
90
91 // if(File.separatorChar == ':') {
92 // if(macFileSystemView == null) {
93 // macFileSystemView = new MacFileSystemView();
94 // }
95 // return macFileSystemView;
96 //}
97
98 if(genericFileSystemView == null) {
99 genericFileSystemView = new GenericFileSystemView();
100 }
101 return genericFileSystemView;
102 }
103
104 public FileSystemView() {
105 final WeakReference<FileSystemView> weakReference = new WeakReference<FileSystemView>(this);
106
107 UIManager.addPropertyChangeListener(new PropertyChangeListener() {
108 public void propertyChange(PropertyChangeEvent evt) {
109 FileSystemView fileSystemView = weakReference.get();
110
111 if (fileSystemView == null) {
112 // FileSystemView was destroyed
113 UIManager.removePropertyChangeListener(this);
114 } else {
115 if (evt.getPropertyName().equals("lookAndFeel")) {
116 fileSystemView.useSystemExtensionHiding =
117 UIManager.getDefaults().getBoolean("FileChooser.useSystemExtensionHiding");
118 }
119 }
120 }
121 });
122 }
123
124 /**
125 * Determines if the given file is a root in the navigable tree(s).
126 * Examples: Windows 98 has one root, the Desktop folder. DOS has one root
127 * per drive letter, <code>C:\</code>, <code>D:\</code>, etc. Unix has one root,
128 * the <code>"/"</code> directory.
129 *
130 * The default implementation gets information from the <code>ShellFolder</code> class.
131 *
132 * @param f a <code>File</code> object representing a directory
133 * @return <code>true</code> if <code>f</code> is a root in the navigable tree.
134 * @see #isFileSystemRoot
135 */
136 public boolean isRoot(File f) {
137 if (f == null || !f.isAbsolute()) {
138 return false;
139 }
140
141 File[] roots = getRoots();
142 for (File root : roots) {
143 if (root.equals(f)) {
144 return true;
145 }
146 }
147 return false;
148 }
149
150 /**
151 * Returns true if the file (directory) can be visited.
152 * Returns false if the directory cannot be traversed.
153 *
154 * @param f the <code>File</code>
155 * @return <code>true</code> if the file/directory can be traversed, otherwise <code>false</code>
156 * @see JFileChooser#isTraversable
157 * @see FileView#isTraversable
158 * @since 1.4
159 */
160 public Boolean isTraversable(File f) {
161 return Boolean.valueOf(f.isDirectory());
162 }
163
164 /**
165 * Name of a file, directory, or folder as it would be displayed in
166 * a system file browser. Example from Windows: the "M:\" directory
167 * displays as "CD-ROM (M:)"
168 *
169 * The default implementation gets information from the ShellFolder class.
170 *
171 * @param f a <code>File</code> object
172 * @return the file name as it would be displayed by a native file chooser
173 * @see JFileChooser#getName
174 * @since 1.4
175 */
176 public String getSystemDisplayName(File f) {
177 if (f == null) {
178 return null;
179 }
180
181 String name = f.getName();
182
183 if (!name.equals("..") && !name.equals(".") &&
184 (useSystemExtensionHiding || !isFileSystem(f) || isFileSystemRoot(f)) &&
185 (f instanceof ShellFolder || f.exists())) {
186
187 try {
188 name = getShellFolder(f).getDisplayName();
189 } catch (FileNotFoundException e) {
190 return null;
191 }
192
193 if (name == null || name.length() == 0) {
194 name = f.getPath(); // e.g. "/"
195 }
196 }
197
198 return name;
199 }
200
201 /**
202 * Type description for a file, directory, or folder as it would be displayed in
203 * a system file browser. Example from Windows: the "Desktop" folder
204 * is described as "Desktop".
205 *
206 * Override for platforms with native ShellFolder implementations.
207 *
208 * @param f a <code>File</code> object
209 * @return the file type description as it would be displayed by a native file chooser
210 * or null if no native information is available.
211 * @see JFileChooser#getTypeDescription
212 * @since 1.4
213 */
214 public String getSystemTypeDescription(File f) {
215 return null;
216 }
217
218 /**
219 * Icon for a file, directory, or folder as it would be displayed in
220 * a system file browser. Example from Windows: the "M:\" directory
221 * displays a CD-ROM icon.
222 *
223 * The default implementation gets information from the ShellFolder class.
224 *
225 * @param f a <code>File</code> object
226 * @return an icon as it would be displayed by a native file chooser
227 * @see JFileChooser#getIcon
228 * @since 1.4
229 */
230 public Icon getSystemIcon(File f) {
231 if (f == null) {
232 return null;
233 }
234
235 ShellFolder sf;
236
237 try {
238 sf = getShellFolder(f);
239 } catch (FileNotFoundException e) {
240 return null;
241 }
242
243 Image img = sf.getIcon(false);
244
245 if (img != null) {
246 return new ImageIcon(img, sf.getFolderType());
247 } else {
248 return UIManager.getIcon(f.isDirectory() ? "FileView.directoryIcon" : "FileView.fileIcon");
249 }
250 }
251
252 /**
253 * On Windows, a file can appear in multiple folders, other than its
254 * parent directory in the filesystem. Folder could for example be the
255 * "Desktop" folder which is not the same as file.getParentFile().
256 *
257 * @param folder a <code>File</code> object representing a directory or special folder
258 * @param file a <code>File</code> object
259 * @return <code>true</code> if <code>folder</code> is a directory or special folder and contains <code>file</code>.
260 * @since 1.4
261 */
262 public boolean isParent(File folder, File file) {
263 if (folder == null || file == null) {
264 return false;
265 } else if (folder instanceof ShellFolder) {
266 File parent = file.getParentFile();
267 if (parent != null && parent.equals(folder)) {
268 return true;
269 }
270 File[] children = getFiles(folder, false);
271 for (File child : children) {
272 if (file.equals(child)) {
273 return true;
274 }
275 }
276 return false;
277 } else {
278 return folder.equals(file.getParentFile());
279 }
280 }
281
282 /**
283 *
284 * @param parent a <code>File</code> object representing a directory or special folder
285 * @param fileName a name of a file or folder which exists in <code>parent</code>
286 * @return a File object. This is normally constructed with <code>new
287 * File(parent, fileName)</code> except when parent and child are both
288 * special folders, in which case the <code>File</code> is a wrapper containing
289 * a <code>ShellFolder</code> object.
290 * @since 1.4
291 */
292 public File getChild(File parent, String fileName) {
293 if (parent instanceof ShellFolder) {
294 File[] children = getFiles(parent, false);
295 for (File child : children) {
296 if (child.getName().equals(fileName)) {
297 return child;
298 }
299 }
300 }
301 return createFileObject(parent, fileName);
302 }
303
304
305 /**
306 * Checks if <code>f</code> represents a real directory or file as opposed to a
307 * special folder such as <code>"Desktop"</code>. Used by UI classes to decide if
308 * a folder is selectable when doing directory choosing.
309 *
310 * @param f a <code>File</code> object
311 * @return <code>true</code> if <code>f</code> is a real file or directory.
312 * @since 1.4
313 */
314 public boolean isFileSystem(File f) {
315 if (f instanceof ShellFolder) {
316 ShellFolder sf = (ShellFolder)f;
317 // Shortcuts to directories are treated as not being file system objects,
318 // so that they are never returned by JFileChooser.
319 return sf.isFileSystem() && !(sf.isLink() && sf.isDirectory());
320 } else {
321 return true;
322 }
323 }
324
325 /**
326 * Creates a new folder with a default folder name.
327 *
328 * @param containingDir a {@code File} object denoting directory to contain the new folder
329 * @return a {@code File} object denoting the newly created folder
330 * @throws IOException if new folder could not be created
331 */
332 public abstract File createNewFolder(File containingDir) throws IOException;
333
334 /**
335 * Returns whether a file is hidden or not.
336 *
337 * @param f a {@code File} object
338 * @return true if the given {@code File} denotes a hidden file
339 */
340 public boolean isHiddenFile(File f) {
341 return f.isHidden();
342 }
343
344
345 /**
346 * Is dir the root of a tree in the file system, such as a drive
347 * or partition. Example: Returns true for "C:\" on Windows 98.
348 *
349 * @param dir a <code>File</code> object representing a directory
350 * @return <code>true</code> if <code>f</code> is a root of a filesystem
351 * @see #isRoot
352 * @since 1.4
353 */
354 public boolean isFileSystemRoot(File dir) {
355 return ShellFolder.isFileSystemRoot(dir);
356 }
357
358 /**
359 * Used by UI classes to decide whether to display a special icon
360 * for drives or partitions, e.g. a "hard disk" icon.
361 *
362 * The default implementation has no way of knowing, so always returns false.
363 *
364 * @param dir a directory
365 * @return <code>false</code> always
366 * @since 1.4
367 */
368 public boolean isDrive(File dir) {
369 return false;
370 }
371
372 /**
373 * Used by UI classes to decide whether to display a special icon
374 * for a floppy disk. Implies isDrive(dir).
375 *
376 * The default implementation has no way of knowing, so always returns false.
377 *
378 * @param dir a directory
379 * @return <code>false</code> always
380 * @since 1.4
381 */
382 public boolean isFloppyDrive(File dir) {
383 return false;
384 }
385
386 /**
387 * Used by UI classes to decide whether to display a special icon
388 * for a computer node, e.g. "My Computer" or a network server.
389 *
390 * The default implementation has no way of knowing, so always returns false.
391 *
392 * @param dir a directory
393 * @return <code>false</code> always
394 * @since 1.4
395 */
396 public boolean isComputerNode(File dir) {
397 return ShellFolder.isComputerNode(dir);
398 }
399
400
401 /**
402 * Returns all root partitions on this system. For example, on
403 * Windows, this would be the "Desktop" folder, while on DOS this
404 * would be the A: through Z: drives.
405 *
406 * @return an array of {@code File} objects representing all root partitions
407 * on this system
408 */
409 public File[] getRoots() {
410 // Don't cache this array, because filesystem might change
411 File[] roots = (File[])ShellFolder.get("roots");
412
413 for (int i = 0; i < roots.length; i++) {
414 if (isFileSystemRoot(roots[i])) {
415 roots[i] = createFileSystemRoot(roots[i]);
416 }
417 }
418 return roots;
419 }
420
421
422 // Providing default implementations for the remaining methods
423 // because most OS file systems will likely be able to use this
424 // code. If a given OS can't, override these methods in its
425 // implementation.
426
427 public File getHomeDirectory() {
428 return createFileObject(System.getProperty("user.home"));
429 }
430
431 /**
432 * Return the user's default starting directory for the file chooser.
433 *
434 * @return a <code>File</code> object representing the default
435 * starting folder
436 * @since 1.4
437 */
438 public File getDefaultDirectory() {
439 File f = (File)ShellFolder.get("fileChooserDefaultFolder");
440 if (isFileSystemRoot(f)) {
441 f = createFileSystemRoot(f);
442 }
443 return f;
444 }
445
446 /**
447 * Returns a File object constructed in dir from the given filename.
448 *
449 * @param dir an abstract pathname denoting a directory
450 * @param filename a {@code String} representation of a pathname
451 * @return a {@code File} object created from {@code dir} and {@code filename}
452 */
453 public File createFileObject(File dir, String filename) {
454 if(dir == null) {
455 return new File(filename);
456 } else {
457 return new File(dir, filename);
458 }
459 }
460
461 /**
462 * Returns a File object constructed from the given path string.
463 *
464 * @param path {@code String} representation of path
465 * @return a {@code File} object created from the given {@code path}
466 */
467 public File createFileObject(String path) {
468 File f = new File(path);
469 if (isFileSystemRoot(f)) {
470 f = createFileSystemRoot(f);
471 }
472 return f;
473 }
474
475
476 /**
477 * Gets the list of shown (i.e. not hidden) files.
478 *
479 * @param dir the root directory of files to be returned
480 * @param useFileHiding determine if hidden files are returned
481 * @return an array of {@code File} objects representing files and
482 * directories in the given {@code dir}. It includes hidden
483 * files if {@code useFileHiding} is false.
484 */
485 public File[] getFiles(File dir, boolean useFileHiding) {
486 List<File> files = new ArrayList<File>();
487
488 // add all files in dir
489 if (!(dir instanceof ShellFolder)) {
490 try {
491 dir = getShellFolder(dir);
492 } catch (FileNotFoundException e) {
493 return new File[0];
494 }
495 }
496
497 File[] names = ((ShellFolder) dir).listFiles(!useFileHiding);
498
499 if (names == null) {
500 return new File[0];
501 }
502
503 for (File f : names) {
504 if (Thread.currentThread().isInterrupted()) {
505 break;
506 }
507
508 if (!(f instanceof ShellFolder)) {
509 if (isFileSystemRoot(f)) {
510 f = createFileSystemRoot(f);
511 }
512 try {
513 f = ShellFolder.getShellFolder(f);
514 } catch (FileNotFoundException e) {
515 // Not a valid file (wouldn't show in native file chooser)
516 // Example: C:\pagefile.sys
517 continue;
518 } catch (InternalError e) {
519 // Not a valid file (wouldn't show in native file chooser)
520 // Example C:\Winnt\Profiles\joe\history\History.IE5
521 continue;
522 }
523 }
524 if (!useFileHiding || !isHiddenFile(f)) {
525 files.add(f);
526 }
527 }
528
529 return files.toArray(new File[files.size()]);
530 }
531
532
533
534 /**
535 * Returns the parent directory of <code>dir</code>.
536 * @param dir the <code>File</code> being queried
537 * @return the parent directory of <code>dir</code>, or
538 * <code>null</code> if <code>dir</code> is <code>null</code>
539 */
540 public File getParentDirectory(File dir) {
541 if (dir == null || !dir.exists()) {
542 return null;
543 }
544
545 ShellFolder sf;
546
547 try {
548 sf = getShellFolder(dir);
549 } catch (FileNotFoundException e) {
550 return null;
551 }
552
553 File psf = sf.getParentFile();
554
555 if (psf == null) {
556 return null;
557 }
558
559 if (isFileSystem(psf)) {
560 File f = psf;
561 if (!f.exists()) {
562 // This could be a node under "Network Neighborhood".
563 File ppsf = psf.getParentFile();
564 if (ppsf == null || !isFileSystem(ppsf)) {
565 // We're mostly after the exists() override for windows below.
566 f = createFileSystemRoot(f);
567 }
568 }
569 return f;
570 } else {
571 return psf;
572 }
573 }
574
575 /**
576 * Throws {@code FileNotFoundException} if file not found or current thread was interrupted
577 */
578 ShellFolder getShellFolder(File f) throws FileNotFoundException {
579 if (!(f instanceof ShellFolder) && !(f instanceof FileSystemRoot) && isFileSystemRoot(f)) {
580 f = createFileSystemRoot(f);
581 }
582
583 try {
584 return ShellFolder.getShellFolder(f);
585 } catch (InternalError e) {
586 System.err.println("FileSystemView.getShellFolder: f="+f);
587 e.printStackTrace();
588 return null;
589 }
590 }
591
592 /**
593 * Creates a new <code>File</code> object for <code>f</code> with correct
594 * behavior for a file system root directory.
595 *
596 * @param f a <code>File</code> object representing a file system root
597 * directory, for example "/" on Unix or "C:\" on Windows.
598 * @return a new <code>File</code> object
599 * @since 1.4
600 */
601 protected File createFileSystemRoot(File f) {
602 return new FileSystemRoot(f);
603 }
604
605 @SuppressWarnings("serial") // Same-version serialization only
606 static class FileSystemRoot extends File {
607 public FileSystemRoot(File f) {
608 super(f,"");
609 }
610
611 public FileSystemRoot(String s) {
612 super(s);
613 }
614
615 public boolean isDirectory() {
616 return true;
617 }
618
619 public String getName() {
620 return getPath();
621 }
622 }
623 }
624
625 /**
626 * FileSystemView that handles some specific unix-isms.
627 */
628 class UnixFileSystemView extends FileSystemView {
629
630 private static final String newFolderString =
631 UIManager.getString("FileChooser.other.newFolder");
632 private static final String newFolderNextString =
633 UIManager.getString("FileChooser.other.newFolder.subsequent");
634
635 /**
636 * Creates a new folder with a default folder name.
637 */
638 public File createNewFolder(File containingDir) throws IOException {
639 if(containingDir == null) {
640 throw new IOException("Containing directory is null:");
641 }
642 File newFolder;
643 // Unix - using OpenWindows' default folder name. Can't find one for Motif/CDE.
644 newFolder = createFileObject(containingDir, newFolderString);
645 int i = 1;
646 while (newFolder.exists() && i < 100) {
647 newFolder = createFileObject(containingDir, MessageFormat.format(
648 newFolderNextString, new Integer(i)));
649 i++;
650 }
651
652 if(newFolder.exists()) {
653 throw new IOException("Directory already exists:" + newFolder.getAbsolutePath());
654 } else {
655 newFolder.mkdirs();
656 }
657
658 return newFolder;
659 }
660
661 public boolean isFileSystemRoot(File dir) {
662 return dir != null && dir.getAbsolutePath().equals("/");
663 }
664
665 public boolean isDrive(File dir) {
666 return isFloppyDrive(dir);
667 }
668
669 public boolean isFloppyDrive(File dir) {
670 // Could be looking at the path for Solaris, but wouldn't be reliable.
671 // For example:
672 // return (dir != null && dir.getAbsolutePath().toLowerCase().startsWith("/floppy"));
673 return false;
674 }
675
676 public boolean isComputerNode(File dir) {
677 if (dir != null) {
678 String parent = dir.getParent();
679 if (parent != null && parent.equals("/net")) {
680 return true;
681 }
682 }
683 return false;
684 }
685 }
686
687
688 /**
689 * FileSystemView that handles some specific windows concepts.
690 */
691 class WindowsFileSystemView extends FileSystemView {
692
693 private static final String newFolderString =
694 UIManager.getString("FileChooser.win32.newFolder");
695 private static final String newFolderNextString =
696 UIManager.getString("FileChooser.win32.newFolder.subsequent");
697
698 public Boolean isTraversable(File f) {
699 return Boolean.valueOf(isFileSystemRoot(f) || isComputerNode(f) || f.isDirectory());
700 }
701
702 public File getChild(File parent, String fileName) {
703 if (fileName.startsWith("\\")
704 && !fileName.startsWith("\\\\")
705 && isFileSystem(parent)) {
706
707 //Path is relative to the root of parent's drive
708 String path = parent.getAbsolutePath();
709 if (path.length() >= 2
710 && path.charAt(1) == ':'
711 && Character.isLetter(path.charAt(0))) {
712
713 return createFileObject(path.substring(0, 2) + fileName);
714 }
715 }
716 return super.getChild(parent, fileName);
717 }
718
719 /**
720 * Type description for a file, directory, or folder as it would be displayed in
721 * a system file browser. Example from Windows: the "Desktop" folder
722 * is described as "Desktop".
723 *
724 * The Windows implementation gets information from the ShellFolder class.
725 */
726 public String getSystemTypeDescription(File f) {
727 if (f == null) {
728 return null;
729 }
730
731 try {
732 return getShellFolder(f).getFolderType();
733 } catch (FileNotFoundException e) {
734 return null;
735 }
736 }
737
738 /**
739 * @return the Desktop folder.
740 */
741 public File getHomeDirectory() {
742 return getRoots()[0];
743 }
744
745 /**
746 * Creates a new folder with a default folder name.
747 */
748 public File createNewFolder(File containingDir) throws IOException {
749 if(containingDir == null) {
750 throw new IOException("Containing directory is null:");
751 }
752 // Using NT's default folder name
753 File newFolder = createFileObject(containingDir, newFolderString);
754 int i = 2;
755 while (newFolder.exists() && i < 100) {
756 newFolder = createFileObject(containingDir, MessageFormat.format(
757 newFolderNextString, new Integer(i)));
758 i++;
759 }
760
761 if(newFolder.exists()) {
762 throw new IOException("Directory already exists:" + newFolder.getAbsolutePath());
763 } else {
764 newFolder.mkdirs();
765 }
766
767 return newFolder;
768 }
769
770 public boolean isDrive(File dir) {
771 return isFileSystemRoot(dir);
772 }
773
774 public boolean isFloppyDrive(final File dir) {
775 String path = AccessController.doPrivileged(new PrivilegedAction<String>() {
776 public String run() {
777 return dir.getAbsolutePath();
778 }
779 });
780
781 return path != null && (path.equals("A:\\") || path.equals("B:\\"));
782 }
783
784 /**
785 * Returns a File object constructed from the given path string.
786 */
787 public File createFileObject(String path) {
788 // Check for missing backslash after drive letter such as "C:" or "C:filename"
789 if (path.length() >= 2 && path.charAt(1) == ':' && Character.isLetter(path.charAt(0))) {
790 if (path.length() == 2) {
791 path += "\\";
792 } else if (path.charAt(2) != '\\') {
793 path = path.substring(0, 2) + "\\" + path.substring(2);
794 }
795 }
796 return super.createFileObject(path);
797 }
798
799 @SuppressWarnings("serial") // anonymous class
800 protected File createFileSystemRoot(File f) {
801 // Problem: Removable drives on Windows return false on f.exists()
802 // Workaround: Override exists() to always return true.
803 return new FileSystemRoot(f) {
804 public boolean exists() {
805 return true;
806 }
807 };
808 }
809
810 }
811
812 /**
813 * Fallthrough FileSystemView in case we can't determine the OS.
814 */
815 class GenericFileSystemView extends FileSystemView {
816
817 private static final String newFolderString =
818 UIManager.getString("FileChooser.other.newFolder");
819
820 /**
821 * Creates a new folder with a default folder name.
822 */
823 public File createNewFolder(File containingDir) throws IOException {
824 if(containingDir == null) {
825 throw new IOException("Containing directory is null:");
826 }
827 // Using NT's default folder name
828 File newFolder = createFileObject(containingDir, newFolderString);
829
830 if(newFolder.exists()) {
831 throw new IOException("Directory already exists:" + newFolder.getAbsolutePath());
832 } else {
833 newFolder.mkdirs();
834 }
835
836 return newFolder;
837 }
838
839 }