code: public static String collectLicenseFieldsForSignature(final Map<String, String> properties) {
  
  		final StringBuilder buf = new StringBuilder();
  
  		buf.append(properties.get(NameKey));
  		buf.append(properties.get(DateKey));
  		buf.append(properties.get(StartKey));
  		buf.append(properties.get(EndKey));
  		buf.append(properties.get(EditionKey));
  		buf.append(properties.get(ModulesKey));
  		buf.append(properties.get(MachineKey));
  
  		// optional values
  		final String servers = properties.get(ServersKey);
  		if (StringUtils.isNotBlank(servers)) {
  
  			buf.append(servers);
  		}
  
  		final String users = properties.get(UsersKey);
  		if (StringUtils.isNotBlank(users)) {
  
  			buf.append(users);
  		}
  
  		return buf.toString();
  	}
docs: ----- private static methods -----