String returnValue = null;
try {
if (user != null) {
IRolesHandler rolesHandlerClass = (IRolesHandler) Class.forName(rolesHandler).newInstance();
List roles = rolesHandlerClass.calculateRoles(parameters);
Integer id = EventsManager.getInstance().registerEvent(user,description, parameters, roles, presentationHandler);
returnValue = id.toString();
logger.debug("Service executed succesfully");
} else {
logger.warn("User is NULL");