public PolicyConfigLoader setClientResultHandler(Handler<List<Client>> clientResultHandler) {
        this.clientResultHandler = clientResultHandler;
        return this;
    }
Set the client result handler, invoked when Clients have been unmarshalled successfully.
@param clientResultHandler the handler
@return fluent
gateway/engine/vertx-polling/src/main/java/io/apiman/gateway/engine/vertx/polling/PolicyConfigLoader.java