做网站搞什么流量,wordpress主题绑定域名,南宁网站建设 醉懂网络,wordpress 重装界面在java开发中#xff0c;习惯使用Handler、Message来处理同步#xff0c;比如对相机的操作(open、setParamters、start、stop、clost)全部抛到同一个线程处理#xff0c;防止并发操作导致异常#xff0c;这样保留给外部的统一接口就是安全的#xff0c;无论外部哪些线程来…在java开发中习惯使用Handler、Message来处理同步比如对相机的操作(open、setParamters、start、stop、clost)全部抛到同一个线程处理防止并发操作导致异常这样保留给外部的统一接口就是安全的无论外部哪些线程来调用最终到控制模块都是在同一线程处理相机操作。这里提供一个C实现的Handler Message封装可以实现类似安卓那样的接口
Handler类封装 #ifndef _CPP_THREADHANDLER_H
#define _CPP_THREADHANDLER_H#include algorithm
#include chrono
#include condition_variable
#include functional
#include iostream
#include list
#include map
#include memory
#include mutex
#include thread
#include Message.hclass ThreadHandler {public:using TimePoint_t std::chrono::steady_clock::time_point;using Clock_t std::chrono::steady_clock;using MillisDuration_t std::chrono::milliseconds;using Task std::functionvoid(const Message msg);ThreadHandler() : _stoped(false) { initLoop(); }~ThreadHandler() {_stoped true;_cond.notify_all();_looper.join();}void setName(const std::string n) { this-name n; }bool sendEmptyMessageDelay(int what, long delay_millis) {if (what 0 || delay_millis 0)return false;Message msg(what, delay_millis);std::unique_lockstd::mutex lock(_queue_lock);_msg_list.push_back(msg);_msg_list.sort(std::lessMessage());_cond.notify_all();return true;}bool sendEmptyMessageDelay(int what) {return sendEmptyMessageDelay(what, 0);}bool postDelay(std::functionvoid() f, long delay_millis) {if (f nullptr || delay_millis 0) {return false;}std::unique_lockstd::mutex lock(_queue_lock);Message msg(0, delay_millis);msg.onRun(std::move(f));_msg_list.push_back(msg);_msg_list.sort(std::lessMessage());_cond.notify_all();return true;}bool post(std::functionvoid() f) { return postDelay(std::move(f), 0); }void removeMessages(int what) {if (what 0)return;std::unique_lockstd::mutex lock(_queue_lock);if (!_msg_list.empty())_msg_list.remove_if([what](const Message m) { return m.what what; });}void removeAlls() {std::unique_lockstd::mutex lock(_queue_lock);if (!_msg_list.empty())_msg_list.clear();printf(ThreadHandler::removeAlls name: %s,name.c_str());}void stop() {_stoped true;_cond.notify_all();printf(ThreadHandler::stop name: %s, name.c_str());}void handleMessage(Task cb) { _callback cb; }private:void dispatchMessage(const Message msg) const {if (msg.task ! nullptr) {msg.task();} else {if (msg.what 0 || _callback nullptr)return;_callback(msg);}}void initLoop() {_looper std::thread([this]() {while (true) {Message msg;bool isFired false;{std::unique_lockstd::mutex lock(_queue_lock);if (_msg_list.empty()) {_cond.wait(lock, [this] {return _stoped || !_msg_list.empty();});} else {auto front _msg_list.front();// 如果要when 大于 当前时间则休眠否则继续往下执行if (front.when Clock_t::now()) {if (front.when Clock_t::now() maxSleepTime) {printf(ThreadHandler::initLoop time too long name: %s, when: %s ,now: %s , maxSleepTime: %s,name.c_str(),std::to_string(std::chrono::duration_caststd::chrono::seconds(front.when.time_since_epoch()).count()).c_str(),std::to_string(std::chrono::duration_caststd::chrono::seconds(Clock_t::now().time_since_epoch()).count()).c_str(),std::to_string(std::chrono::duration_caststd::chrono::seconds(maxSleepTime).count()).c_str());}_cond.wait_until(lock, front.when, [this] {return _stoped || (!_msg_list.empty() _msg_list.front().when Clock_t::now());});}}if (!_stoped _msg_list.empty())continue;if (_stoped) {_msg_list.clear();return;}// List的头结点的时间小于等于当前时间则执行头结点任务if (_msg_list.front().when Clock_t::now()) {msg std::move(_msg_list.front());_msg_list.pop_front();isFired true;}}if (isFired) {dispatchMessage(msg);}}});}bool _stoped;std::string name;std::listMessage _msg_list;std::mutex _queue_lock;std::condition_variable _cond;std::thread _looper;Task _callback;std::chrono::minutes maxSleepTime{4};
};#endif // _CPP_THREADHANDLER_HMessage实现类 #ifndef _CPP_MESSAGE_H
#define _CPP_MESSAGE_H
#include chrono
#include condition_variable
#include functional
#include iostream
#include list
#include map
#include memory
#include mutex
#include threadclass Message {public:using TimePoint_t std::chrono::steady_clock::time_point;using Clock_t std::chrono::steady_clock;using MillisDuration_t std::chrono::milliseconds;int what;int m_arg1;int m_arg2;std::functionvoid() task;TimePoint_t when;Message() : Message(-1, 0) {}Message(int what) : Message(what, 0) {}Message(int what, long delayMillis): what(what), when(Clock_t::now() MillisDuration_t(delayMillis)) {task nullptr;}Message(const Message msg): what(msg.what), task(msg.task), when(msg.when) {}Message(Message msg) : what(msg.what), task(msg.task), when(msg.when) {}~Message() {}Message operator(const Message msg) {this-what msg.what;this-when msg.when;this-task msg.task;return *this;}Message operator(Message msg) {this-what msg.what;this-when msg.when;this-task std::move(msg.task);return *this;}void setWhen(long delayMillis) {when Clock_t::now() MillisDuration_t(delayMillis);}void onRun(std::functionvoid() f) { this-task f; }bool operator(const Message msg) const { return (this-when msg.when); }bool operator(const Message msg) const { return (this-when msg.when); }bool operator(const Message msg) const {return (this-what msg.what) (this-task ! nullptr) (msg.task ! nullptr);}bool operator(int what) const { return (this-what what); }
};#endif // _CPP_MESSAGE_H使用方法
//构造函数或类初始化中设置如下
mHandler.setName(classATh);
mHandler.handleMessage([](const Message msg) { handleMessage(msg); }); void classATh::handleMessage(const Message msg) { if (msg.what MSG_CODE_QUERY_DEVICE_INFO) { // } else if (msg.what MSG_CODE_TRADE_INIT) { // } else if (msg.what MSG_CODE_DEVICE_HEART_BEAT) { heartBeat(); }
}
void classATh::startHearBeat() { mHandler.removeMessages(MSG_CODE_DEVICE_HEART_BEAT); mHandler.sendEmptyMessageDelay(MSG_CODE_DEVICE_HEART_BEAT, 60 * 1000);
}
