Material Google Drive SDK para fazer backup/restauração do banco de dados de App

@SuppressWarnings("resource")
private void exportDatabase(Context ctx) {

	File backupDB = null;
	try {
		File sd = Environment.getExternalStorageDirectory();
		File data = Environment.getDataDirectory();

		if (sd.canWrite()) {

			String currentDBPath = "//data//" + ctx.getPackageName()
					+ "//databases//" + "NomeDoBanco.db";
			File currentDB = new File(data, currentDBPath);
			backupDB = new File(sd, "NomeDoBanco.db");

			if (currentDB.exists()) {
				FileChannel src = new FileInputStream(currentDB).getChannel();
				FileChannel dst = new FileOutputStream(backupDB).getChannel();
				dst.transferFrom(src, 0, src.size());                    
				src.close();
				dst.close();
			}
		} else {
			System.out.println("Não pode escrever no sd");
		}

	} catch (Exception e) {
		System.out.println("Exception:" + e);
	}

	try {		
		//Intent para exportar
		Intent intent = new Intent(android.content.Intent.ACTION_SEND);
		intent.setType("*/*");
		intent.putExtra(android.content.Intent.EXTRA_EMAIL, new String[]{});            

		intent.putExtra(android.content.Intent.EXTRA_SUBJECT, "Banco de dados");
		intent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(backupDB));
		ctx.startActivity(Intent.createChooser(intent, "Exportar banco de dados"));
	}catch(Exception e){
		System.out.println("Exception:"+e);
	}
}

public void importa(){
	try {		
		String from = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS) + "/NomeDoBanco.db";
		String outFileName = Environment.getDataDirectory() + "//data//" + getContext().getPackageName() + "//databases//NomeDoBanco.db";
		File temp = new File(outFileName);
		if (temp.exists()) {
			temp.delete();
		}

		temp.createNewFile();

		String to = Environment.getDataDirectory() + "//data//" + getContext().getPackageName() + "//databases//";
		ImportarBAnco(from, to);

	} catch (Exception e) {
		System.out.println("Exception:"+e.toString());
	}
}

private void ImportarBAnco(String from, String to) {
	try {
		File sd = Environment.getExternalStorageDirectory();
		if (sd.canWrite()) {
			int end = from.toString().lastIndexOf("/");
			String str1 = from.toString().substring(0, end);
			String str2 = from.toString().substring(end+1, from.length());
			File source = new File(str1, str2);
			File destination= new File(to, str2);
			if (source.exists()) {
				FileChannel src = new FileInputStream(source).getChannel();
				FileChannel dst = new FileOutputStream(destination).getChannel();
				dst.transferFrom(src, 0, src.size());
				src.close();
				dst.close();
				System.out.println("Importado com sucesso");
			}else{
				System.out.println("Source não existe");
			}
		}else{
			System.out.println("Não tem permissão");
		}

	} catch (Exception e) {
		System.out.println("Erro ao importar:"+e.toString());
	}
}