做游戏视频网站要批证吗杭州seo排名优化外包

介绍

建造者模式是一种创建型的设计模式 它用于分步骤构建复杂对象

核心思想

它的核心思想就是将复杂对象部件的创建和组装过程抽象出来

代码示例

class SpeechServer {public:using ptr = std::shared_ptr<SpeechServer>;SpeechServer(const ASRClient::ptr asr_client, const Registry::ptr &reg_client,const std::shared_ptr<brpc::Server> &server):_asr_client(asr_client),_reg_client(reg_client),_rpc_server(server){}~SpeechServer(){}//搭建RPC服务器，并启动服务器void start() {_rpc_server->RunUntilAskedToQuit();}private:ASRClient::ptr _asr_client;Registry::ptr _reg_client;std::shared_ptr<brpc::Server> _rpc_server;
};class SpeechServerBuilder {public://构造语音识别客户端对象void make_asr_object(const std::string &app_id,const std::string &api_key,const std::string &secret_key) {_asr_client = std::make_shared<ASRClient>(app_id, api_key, secret_key);}//用于构造服务注册客户端对象void make_reg_object(const std::string &reg_host,const std::string &service_name,const std::string &access_host) {_reg_client = std::make_shared<Registry>(reg_host);_reg_client->registry(service_name, access_host);}//构造RPC服务器对象void make_rpc_server(uint16_t port, int32_t timeout, uint8_t num_threads) {if (!_asr_client) {LOG_ERROR("还未初始化语音识别模块！");abort();}_rpc_server = std::make_shared<brpc::Server>();SpeechServiceImpl *speech_service = new SpeechServiceImpl(_asr_client);int ret = _rpc_server->AddService(speech_service, brpc::ServiceOwnership::SERVER_OWNS_SERVICE);if (ret == -1) {LOG_ERROR("添加Rpc服务失败！");abort();}brpc::ServerOptions options;options.idle_timeout_sec = timeout;options.num_threads = num_threads;ret = _rpc_server->Start(port, &options);if (ret == -1) {LOG_ERROR("服务启动失败！");abort();}}SpeechServer::ptr build() {if (!_asr_client) {LOG_ERROR("还未初始化语音识别模块！");abort();}if (!_reg_client) {LOG_ERROR("还未初始化服务注册模块！");abort();}if (!_rpc_server) {LOG_ERROR("还未初始化RPC服务器模块！");abort();}SpeechServer::ptr server = std::make_shared<SpeechServer>(_asr_client, _reg_client, _rpc_server);return server;}private:ASRClient::ptr _asr_client;Registry::ptr _reg_client;std::shared_ptr<brpc::Server> _rpc_server;
};

就像上面这段代码 如果不用建造者模式的话

我们每创建一个新的server对象就需要自己手动维护一遍

并且每次要添加新的依赖的时候需要重写这些配置的顺序 比较麻烦 而且不符合DRY原则 维护困难