/**
* Returns the parent directory of <code>dir</code>.
*
* @param dir the <code>File</code> being queried
* @return the parent directory of <code>dir</code>, or <code>null</code> if <code>dir</code> is
* <code>null</code>
*/
public File getParentDirectory(File dir) {
if (dir == null || !dir.exists()) {
return null;
}
ShellFolder sf;
try {
sf = getShellFolder(dir);
} catch (FileNotFoundException e) {
return null;
}
File psf = sf.getParentFile();
if (psf == null) {
return null;
}
if (isFileSystem(psf)) {
File f = psf;
if (!f.exists()) {
// This could be a node under "Network Neighborhood".
File ppsf = psf.getParentFile();
if (ppsf == null || !isFileSystem(ppsf)) {
// We're mostly after the exists() override for windows below.
f = createFileSystemRoot(f);
}
}
return f;
} else {
return psf;
}
}
