method loadProperties

static Properties loadProperties(String dirName, String fileName) {
        Properties properties = new Properties();
        if (dirName != null && fileName != null) {
            File dir = new File(dirName);
            File fileProp = new File(dir, fileName);
            if (fileProp.exists()) {
                try (InputStream is = new FileInputStream(fileProp)) {
                    properties.load(is);
                } catch (IOException e) {
                    throw new IllegalArgumentException("There was a problem with reading properties", e);
                }
            } else {
                log.warn("Missing config.properties file!");
            }
        }
        return properties;
    }