public static void rename(String oldname, String newname) {
		try {

			File file = new File(oldname);
			if (!file.exists()) {
				throw new FileNotFoundException("the old file is not exist!");
			}

			File newFile = new File(newname);
			if (newFile.exists()) {
				throw new IllegalStateException("the new file is exist!");
			}

			file.renameTo(newFile);
		} catch (Exception e) {
			throw Lang.uncheck(e);
		}
	}