title | date |
---|---|
Recursively Move a Directory |
2019-01-09 17:00:00 |
This article shows one effective implementation that follows the Visitor Pattern to recursively move a directory using Java NIO library.
public static void move(Path source, Path target) throws IOException {
class FileMover extends SimpleFileVisitor<Path> {
private Path source;
private Path target;
private FileMover(Path source, Path target) {
this.source = source;
this.target = target;
}
@Override
public FileVisitResult visitFile(final Path file, final BasicFileAttributes attrs) throws IOException {
Path newFile = target.resolve(source.relativize(file));
Files.move(file, newFile,
StandardCopyOption.REPLACE_EXISTING);
return FileVisitResult.CONTINUE;
}
@Override
public FileVisitResult preVisitDirectory(final Path dir, final BasicFileAttributes attrs) throws IOException {
Path newDir = target.resolve(source.relativize(dir));
try {
Files.copy(dir, newDir,
StandardCopyOption.COPY_ATTRIBUTES,
StandardCopyOption.REPLACE_EXISTING);
} catch (DirectoryNotEmptyException e) {
// ignore and skip
}
return FileVisitResult.CONTINUE;
}
@Override
public FileVisitResult postVisitDirectory(final Path dir, final IOException exc) throws IOException {
Path newDir = target.resolve(source.relativize(dir));
FileTime time = Files.getLastModifiedTime(dir);
Files.setLastModifiedTime(newDir, time);
Files.delete(dir);
return FileVisitResult.CONTINUE;
}
}
FileMover fm = new FileMover(source, target);
EnumSet<FileVisitOption> opts = EnumSet.of(FileVisitOption.FOLLOW_LINKS);
Files.walkFileTree(source, opts, Integer.MAX_VALUE, fm);
}