An unhandled exception of type 'System.StackOverflowException' occurred in System.Core.dll

Question

In my Asp.net MVC project

I have a bootsrapper that initialize a unity-container.

I don't know why, but I get

An unhandled exception of type 'System.StackOverflowException' occurred in System.Core.dll

I have doubled checked and registration is done only in my initializer.

All dependencies are injected in the ctors only.

What could have caused this?

    protected void Application_Start()
    {
        AreaRegistration.RegisterAllAreas();
        WebApiConfig.Register(GlobalConfiguration.Configuration);
        FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
        RouteConfig.RegisterRoutes(RouteTable.Routes);

        Initializer.Initialize();
        BundleConfig.RegisterBundles(BundleTable.Bundles);
    }

It fails after BundleConfig.RegisterBundles(BundleTable.Bundles);

public static class Initializer
{
    private static bool isInitialize;
    private static readonly object LockObj = new object();
    private static IUnityContainer defaultContainer = new UnityContainer();

    static Initializer()
    {
        Initialize();
    }

    public static void Initialize()
    {
        if (isInitialize)
            return;

        lock (LockObj)
        {
            IUnityContainer container = defaultContainer;

            //registering Unity for MVC
            DependencyResolver.SetResolver(new UnityDependencyResolver(container));

            //registering Unity for web API
            //  GlobalConfiguration.Configuration.DependencyResolver = new Unity.WebApi.UnityDependencyResolver(container);

            #region managers
            container.RegisterType<ISettingsManager, SettingsManager>();

            container.RegisterType<IMamDataManager, MamDataManager>();

            container.RegisterType<IAppsDataManager, AppsDataManager>();
            #endregion

            #region Dals
            container.RegisterType<IDal<ClientService.DAL.EntityFramework.App>, AppsDal>();

            #endregion Dals

            #region cache
            container.RegisterType<ICache<string, ClientService.DAL.EntityFramework.Group>, GroupsCache>(new ContainerControlledLifetimeManager());

            container.RegisterType<ICache<string, ClientService.DAL.EntityFramework.App>, AppsCache>(new ContainerControlledLifetimeManager());

            container.RegisterType<ICache<string, SettingsServiceData>, SettingsServiceDataCache>(new ContainerControlledLifetimeManager());
            #endregion cache

            #region Pollers
            container.RegisterType<IPoller<ClientService.DAL.EntityFramework.Group>, GroupsPoller>(new ContainerControlledLifetimeManager());

            container.RegisterType<IPoller<ClientService.DAL.EntityFramework.App>, AppsPoller>(new ContainerControlledLifetimeManager());

            container.RegisterType<IPoller<SettingsServiceData>, SettingsPoller>(new ContainerControlledLifetimeManager());



            #endregion Pollers


            container.RegisterType<IDefaultConfigurationGroupSingleton, DefaultConfigurationGroupSingleton>(new ContainerControlledLifetimeManager());

            container.RegisterType<IApplicationLogger, Log4NetLogger>();

            if (!isInitialize)
            {
                isInitialize = true;
            }
        }
    }
}

Answer 1

Without providing code, I guess this is due to a circular dependency. Another possible reason is that you have an improper loop in one of your constructors.

As an example, A class requires an instance of B to be resolved; B class requires an instance of C class to be resolved and C class needs an instance of A to be resolved. This results in an infinite loop:

public class A
{
    public A(B b)
    {
    }
}

public class B
{
    public B(C c)
    {
    }
}

public class C
{
    public C(A a)
    {
    }
}

Answer 2

As Rafael mentioned, this is usually caused by circular dependencies, however if you need these dependencies you can fix it by manually resolving some of them.

For example:

// Register the UnityContainer with itself
container.RegisterInstance<IUnityContainer>(container);

public class A
{
    public A(B b) {}
}

public class B
{
    public B(C c) {}
}

public class C
{
    private readonly IUnityContainer _container;
    private A _a => _container.Resolve<A>();

    public C(IUnityContainer container) {
        _container = container;
    }
}

This means that C can be constructed without needing to know about A until it's time to use it :)