when load the initialize() function in the server from demo\Ice\plugin?

when I run the server in the ice demo Ice\plugin ,I find initialize() function which is in the helloplugin34d.dll ,is called but don't know when it is called.

helloplugin code as follow：
///////////////////////////////////////////////
class HelloPluginI : public Ice::Plugin
{
public:

HelloPluginI(const Ice::CommunicatorPtr& communicator) :
_communicator(communicator)
{cout<<"通信器初始化！"<<endl;
}

void
initialize()
{
cout<<"hello适配器初始化！"<<endl;
Ice::ObjectAdapterPtr adapter = _communicator->createObjectAdapter("Hello");
adapter->add(new HelloI, _communicator->stringToIdentity("hello"));
adapter->activate();
}//为什么会调用这个函数？

void
destroy()
{
cout<<"销毁初始化！"<<endl;
}

private:

Ice::CommunicatorPtr _communicator;
};

};

extern "C"
{

ICE_DECLSPEC_EXPORT ::Ice::Plugin*
createHello(const Ice::CommunicatorPtr& communicator, const string& name, const Ice::StringSeq& args)
{
return new HelloPluginI(communicator);
}

}
/////////////////////////////////////////////////////



the server code as follow：

////////////////////////////////////////////////////
#include <Ice/Ice.h>

using namespace std;

class PluginServer : public Ice::Application
{
public:

virtual int
run(int argc, char* argv[])
{
if(argc > 1)
{
cerr << appName() << ": too many arguments" << endl;
return EXIT_FAILURE;
}

communicator()->waitForShutdown();
return EXIT_SUCCESS;
}
};

int
main(int argc, char* argv[])
{
PluginServer app;
return app.main(argc, argv, "config.server");
}
//////////////////////////////////////////////////////



the config.server code as follow :
//////////////////////////////////////////////////////
#
# Warn about connection exceptions
#
Ice.Warn.Connections=1

#
# Network Tracing
#
# 0 = no network tracing
# 1 = trace connection establishment and closure
# 2 = like 1, but more detailed
# 3 = like 2, but also trace data transfer
#
Ice.Trace.Network=1

#
# Protocol Tracing
#
# 0 = no protocol tracing
# 1 = trace protocol messages
#
#Ice.Trace.Protocol=1

#
# Logger Plugin Configuration
#
Ice.Plugin.Logger=LoggerPlugin:createLogger

#
# Hello Plugin Configuration
#
Ice.Plugin.Hello=HelloPlugin:createHello
Hello.Endpoints=tcp -p 10000
//////////////////////////////////////////



I trace the sever runing ,when the code run
///////////////////////////////////////////
class PluginServer : public Ice::Application
{
public:

virtual int
run(int argc, char* argv[])

//////////////////////////////////////////




I find the initialize() function has been called ！but I don't know when it is called ?
could you tell me ?
thank you very much ..