smartfox – Creating jar file for SFS2X is making issue

I created a test script to explore Smartfoxserver 2X(SFS 2X). In Eclipse I created 2 classes for math Handler with the SFS plugin. and I export the project as a .jar file. Then I place the jar file in this path SmartFoxServer_2XSFS2XextensionsmyExt, then started the server. The server is getting close, It’s not working. I checked a lot of tutorials all are using the same method. I don’t know what was the issue. If anyone knows please help.

Class 1:

package com.smartFoxServerPracticeOne;    
import com.smartfoxserver.v2.extensions.SFSExtension;

public class GameManagerReq extends SFSExtension {    
    @Override
    public void init() {
        // TODO Auto-generated method stub
        this.addRequestHandler("math", MathHandler.class);
    }    
}

Class 2:

package com.smartFoxServerPracticeOne;

import com.smartfoxserver.v2.entities.User;
import com.smartfoxserver.v2.entities.data.ISFSObject;
import com.smartfoxserver.v2.entities.data.SFSObject;
import com.smartfoxserver.v2.extensions.BaseClientRequestHandler;

public class MathHandler extends BaseClientRequestHandler {

    @Override
    public void handleClientRequest(User player, ISFSObject params) {
        int n1 = params.getInt("n1");
        int n2 = params.getInt("n2");
        
        ISFSObject rtn = new SFSObject();
        rtn.putInt("sum", n1 + n2);
        
        GameManagerReq parentEx = (GameManagerReq) getParentExtension();
        parentEx.send("math", rtn, player);
    }
}