I have solved the problem it was because i instantiated the class MySec.java it have to be injected in the managed bean not instantiated
@Named
@RequestScoped
public class buttonController {
@EJB mySec myClass;
public buttonController(){
}
public void adminMethod()
{
if(myClass.ifManager())
FacesContext.getCurrentInstance().addMessage(null, new FacesMessage(FacesMessage.SEVERITY_INFO,"Hello Manager", ""));
}
}