<分区>
我的类使用接口(interface)，如果在对象创建时使用了接口(interface)，则需要信息:
界面:
class IServerSetup {
public:
virtual void ServerSetup () = 0;
}
类(class):
class MyServer : public MqC, public IServerSetup {
public:
MyServer(MqS *tmpl) : MqC(tmpl) {};
private:
// service to serve all incomming requests for token "HLWO"
void MyFirstService () {
SendSTART();
SendC("Hello World");
SendRETURN();
}
// define a service as link between the token "HLWO" and the callback "MyFirstService"
void ServerSetup() {
ServiceCreate("HLWO", CallbackF(&MyServer::MyFirstService));
}
};
MqC 的构造函数:
MqC::MqC (struct MqS *tmpl) {
if (tmpl && (*(int*)tmpl) != MQ_MqS_SIGNATURE) {
throw MqCSignatureException("MqS");
} else {
hdl = MqContextCreate(0, tmpl);
MqConfigSetSelf (hdl, this);
this->objInit(); <<<<<<<<<<<< This is the important part…
}
}
现在 objInit() 应该检测接口(interface)以正确配置对象......
void MqC::objInit () {
// use "hdl->setup.Parent.fCreate" to ckeck in context was initialized
if (hdl->setup.Parent.fCreate != NULL) return;
hdl->setup.Parent.fCreate = MqLinkDefault;
hdl->setup.Child.fCreate = MqLinkDefault;
// init the server interface
IServerSetup * const iSetup = dynamic_cast<IServerSetup*const>(this);
if (iSetup != NULL) {
struct ProcCallS * ptr = (struct ProcCallS *) MqSysMalloc(MQ_ERROR_PANIC, sizeof(*ptr));
ptr->type = ProcCallS::PC_IServerSetup;
ptr->call.ServerSetup = iSetup;
MqConfigSetServerSetup (hdl, ProcCall, static_cast<MQ_PTR>(ptr), ProcFree, ProcCopy);
}
...
为了让它更短......行:
IServerSetup * const iSetup = dynamic_cast<IServerSetup*const>(this);
Does not work in a constructor (return always NULL)...所以我需要稍后调用objInit()...这是不好。
更新
如果我在顶层构造函数中使用 objInit...这有效...
→ 但有没有可能避免这种情况(总是重复 objInit())...并在 MqC 构造函数中获取顶级对象？
MyServer(MqS *tmpl) : MqC(tmpl) {
objInit();
};