class PrepareBlockchain {

    public File loadContractFile(ContractVersion version) {
        File contractFile = new File(String.format("%s/%s.jar", contractPath,
                version));
        if (!(contractFile.exists() && contractFile.canRead())) {
            log.error("Contract {} is not exists", version);
            return null;
        }
        return contractFile;
    }

    public  PrepareBlockchain(String contractPath);

}