code: public File createDirectorySync(String prefix) throws IOException {
  		Path path = Files.createTempDirectory(tempDir.toPath(), this.prefix + prefix);
  		File dir = path.toFile();
  		/*
  		app.toClose(new Closeable() {
  			@Override
  			public void close() {
  				new RemoveDirectoryTask(dir, null, 0, null, Task.PRIORITY_NORMAL, false).start();
  			}
  		});*/
  		return dir;
  	}
docs: Create a temporary directory.