OMNeT++: Error in module during network setup: Class not found - eclipse-cdt

Question

I created my first OMNeT++/veins project, but can’t start the simulation.
Can you help me?
I would like to change my question - is there a simple way to create a project, similar to RSUExampleScenario of veins, not under veins/examples/myfolder, but in a separate project and workspace? And what steps must I do for it?
I wanted to create a project similar to RSUExampleScenario from veins, but with other scenario and using other OMNeT++ modules. As I created my project under veins/examples/myfolder, and put my new .ned files under veins structure, it worked fine.
Now I created new project, including folders with .ned and c++/h files, like folder connection (Connection.ned, Connection.cc, Connection.h, package.ned) and folder node (CloudVehicleScenarioMessage.ned, Cloud.ned) and simulation folder cloudvehiclehi (omnetpp.ini).
When I start a simulation I receive the error:
Error in module (cCompoundModule) CloudVehicleScenarioMessage (id=1) during network setup: Class "Connection" not found -- perhaps its code was not linked in, or the class wasn't registered with Register_Class(), or in the case of modules and channels, with Define_Module()/Define_Channel().
I guess the NED files are loaded, but the classes in c++ files cannot be found, though I used Define_Module. Cloud is just a compound module, without any own c++ implementations, it creates no problems. Connection is a simple module, referring to class Connection.cc, where Define_Module() is called and causes the error while loading.
All my folders, like node or connection are included, as I can see under Project->Properties->Paths and Symbols->Includes.
I already tried to rebuild OMNeT++ (as told here https://www.linkedin.com/grp/post/3801609-234767834) and to define namespaces for my classes (as told here Problem in defining a module in omnetpp), but it didn’t help.
I proved my makefile and the folders were linked in (as told here https://groups.google.com/forum/#!topic/omnetpp/Cl48hVgkbQ0).
CloudVehicleScenarioMessage.ned is my network in omnetpp.ini.
nodes/CloudVehicleScenarioMessage.ned:
package cloudbasedcsw.nodes;
import cloudbasedcsw.nodes.ScenarioMobility;
import cloudbasedcsw.nodes.Cloud;
import cloudbasedcsw.connection.Connection;
network CloudVehicleScenarioMessage extends ScenarioMobility
{
#display("bgb=540,555");
submodules:
cloud[1]: Cloud {
#display("p=150,140;b=10,10,oval");
}
con: Connection {
#display("p=200,40;b=10,10,oval");
}
}
ned file of module Connection:
connection/Connection.ned
package cloudbasedcsw.connection;
simple Connection{
#class(CloudBasedCSW::Connection);
}
Class Connection, which can not be found:
connection/Connection.cc
#include <Connection.h>
#include <VehicleListener.h>
#include <iostream>
using CloudBasedCSW::Connection;
Define_Module(CloudBasedCSW::Connection);
void Connection::initialize(int stage){
}
void Connection::connectToCloud(cModule* node){
}
void Connection::disconnectFromCloud(cModule* node){
}
Connection.h
#ifndef CONNECTION_H_
#define CONNECTION_H_
#include <omnetpp.h>
namespace CloudBasedCSW{
class Connection: public cSimpleModule{
public:
cModule* scenario;
void connectToCloud(cModule* node);
void disconnectFromCloud(cModule* node);
protected:
virtual void initialize(int stage);
private:
cModule* cloud;
int currentId;
int gateCloudInId;
int gateCloudOutId;
};
}
#endif /* CONNECTION_H_ */

Answer 1

I guess that your class Connection is in CloudBasedCSW C++ namespace. Therefore in Connection.ned you should change #class(Connection); to #class(CloudBasedCSW::Connection);.

Answer 2

I managed to create a new project and run it, without this error. So, I will share my tutorial.
How to create a OMNeT++ project, which uses veins.
Create omnet++ project myproject File->new->OMNeT project->Empty project with 'src' and 'simulations' folders
Veins must be imported into the workspace in order to use it: Import-> Existing projects into workspace->
Add veins to Project->Properties->Project References
Put your .ned and c++/h files in folder src
Put omnetpp.ini and all sumo configuration files in folder simulations
Create run configuration simulation, with working directory myproject/simulations and Simulation->Executable->Other: with exe file from /myproject/src/myproject
Remark: Don't use namespaces in your c++ files, corresponding to .ned files, because the classes in c++ files would not be found (
Error in module (cCompoundModule) CloudVehicleScenarioMessage (id=1) during network setup: Class "vehicle" not found ).
For Example you have vehicle.ned and vehicle.cc. vehicle.cc
includes a class mynamespace::vehicle. vehicle.ned wouldn't know that vehicle lies under namespace mynamespace. Only if a class is defined in ned file via #class(mynamespace::vehicle), it can be found.

Answer 3

A easy way to correct this error is copying the .cc or all c++ files into a veins/src/ folder. Using this technique you compiler recognize you class.