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using CayenneRuntime in webapplication without web.xml

I have a Wicket application and I'm trying to implement separate configuration that can be changed remotely. That's the end goal, anyway.
What I'm trying to do is set up Cayenne to work by starting it manually, rather than using the web.xml file. I have tried a bunch of different things, but I'm not sure I fully understand how the context is applied to all threads.
I have tried creating a ServerRuntime in my Application class. I've also tried on my custom BasePage class that each page uses. I can get it to kind of work by doing the following on the BasePage, but it is inconsistent:
public class BasePage ....
public static ServerRuntime runtime = new ServerRuntime("cayenne-config.xml");//This is in my BasePage class, but I've also tried this in the Application class
#Override
protected void init() {
BaseContext.bindThreadObjectContext(Application.runtime.getContext());//This is in my BasePage class
}
Like I said, that kind of works, but it isn't consistent. I keep getting errors on
BaseContext.getThreadObjectContext();
Error is this:
java.lang.IllegalStateException: Current thread has no bound ObjectContext.
I can't seem to find much information on this. I tried doing stuff like this, and accessing the runtime using these as well, but nothing is working consistently.
WebUtil.setCayenneRuntime(this.getServletContext(), runtime);
BaseContext.bindThreadObjectContext(WebUtil.getCayenneRuntime(((Application)getApplication()).getServletContext()).getContext());
Any help would be greatly appreciated.

I figured out a way to do this on my own.
I'm extending CayenneFilter and overriding the init method.
In there I copied nearly their exact code. I will be able to check for any config here and load the proper xml file. This obviously isn't the ironed out solution, but is definitely a step forward, and could be the way I end up doing this.
Either way, here's what I have tested to be working.
#WebFilter(filterName = "cayenne-config", displayName = "cayenne-config", urlPatterns = {"/*"})
public class TestFilter extends CayenneFilter
{
#Override
public void init(FilterConfig config) throws ServletException
{
this.checkAlreadyConfigured(config.getServletContext());
this.servletContext = config.getServletContext();
WebConfiguration configAdapter = new WebConfiguration(config);
Collection modules = configAdapter.createModules(new Module[]{new WebModule()});
ServerRuntime runtime = new ServerRuntime("cayenne-test.xml", (Module[])modules.toArray(new Module[modules.size()]));
WebUtil.setCayenneRuntime(config.getServletContext(), runtime);
}
}
I don't think the annotation is needed (I am specifying it all in the web.xml file), but I thought I would leave it here so you could see that it is changing.
If I could find a way to change the config (FilterConfig) values (the init parameters), then I could just change that to the name of the xml file I want to use and not override this entire method. I couldn't figure out how to do that, but I'll look further later.
If anyone has another better answer, I would love to hear it.

togglz annotation based approach for feature validation

I have been using the togglz since last few days.
I am trying to find out if there is annotation based approach available in togglez API.
I want to do it like below -
public class Application {
public static void main(String[] args) {
Application application = new Application();
boolean first=false;
first=application.validate1();
System.out.println(first);
}
#Togglz(feature = "FEATURE_01")
public boolean validate1() {
System.out.println("validate1");
return false;
}
}
Is there anything available in togglz.
I could not find it anywhere , if you have any idea about such annotation please help.
My requirement is to skip the method execution based on feature value passed into it

No, there is no such annotation in Togglz. You will need some framework that support interceptors for that (like Spring, CDI, EJB). Then you can implement such an interceptor yourself.
However, to be honest I'm not sure if such an annotation would make sense. What should be the result if the feature is off? What does the method return? null? Explicit feature checks using a simple if statement are more straight forward to use in theses cases. But that's just my opinion. ;-)

Simple Dependency injection not working

It's the first time I have to use Dependency Injection and I'm a little confused.
I don't really understand how it works.
I have tried on a simple example :
public class StockResponse extends Response
{
#Inject BrandService $brand;
public List<StockResponseItem> stock;
public StockThresholdResponse()
{
stock = new ArrayList<>();
}
public static StockThresholdResponse create(List<DataItem> data)
{
StockResponse stock= new StockResponse();
for (ThresholdCheckAggregate data: d)
{
StockResponseItem item = new StockResponseItem();
item.id = d.thresholdId;
item.brand = str.$brand.byId(d.brand);
str.stockThresholds.add(item);
}
return str;
}
}
But when I use my create() method, I get a null pointer exception for $brand.
I think I have misunderstood how DI works but I can't find my error.

I had similar difficulties to understand how DI (Guice out of Java EE) works. In simple words Guice must have chance to modify You object, for example:
assist by construction usually.
You ask Guice "can You create my object" injector.getInstance(cls), then Guice is creating object for You, solving field or constructor annotation
In normal (non Java EE) environment Yoy never call classic constructor, You ask by second hand.
other method.
Few library / frameworks have integration with Guice (Apache Wicket I personally like) with "creation listeners" on some types of objects. Hard work of DI is hidden for Your eyes, but is executed.
Java EE lets say better EE programmers than me :(
In consequence Yoy don't give chance to inject anything, is null
Professionals sorry that I say at blondie level. That is way like I discovered DI few years ago
Correction to code. Not
StockResponse stock= new StockResponse();
but
mod = .... // Module
injector = Guice.createInjector(mod); // global or almost global
...
injector.getInstance(StockResponse.class);
EDIT: intentionally I don't answer "how to write Guice module", assume this is other, long story

This could work, assuming BrandService is either a concrete class or if it's an interface, you have provided a binding for it to a concrete class elsewhere in your DI configuration (say a module in Guice or Spring #Configuration). I do see one obvious NullPointerException with str variable. Did you mean to do this?
item.brand = stock.$brand.byId(d.brand);

What is the most elegant way to choose what service implementation must be used?

in my controller, I need to choose what service implementation I need to use on spring. Before I was encapsulating this code in a factory, but I think that its not a good practice...
#Component
public class StoreServiceFactory {
#Autowired
private List<StoreService> storeServices;
public StoreService getService(){
if(isActiveSale){
return storeServices.get("PublicStoreService")
}
return storeServices.get("PrivateStoreService")
}
}
So I would like to encapsulate this behaviour to not care about inside my controller.. How can I get it??

If isActiveSale changes when the application is running, I think that what you got is a good solution. Since the Controller is a singleton you can't expect a different injection everytime this value changes.
If you get the value only on the startup of the application(e.g. from some property) you can use a profile.

There is nothing wrong with a factory, although as #R4J points out in the comments it is more of a provider, since it doesn't instantiate anything. I would consider the factory/provider a good choice if the 'isActiveSale' status changes based on things outside of the current control flow, like a configuration in a property file. A setting set in some adminstration screen, or maybe based on the time of day.

Creation of Stateless Components

I have created a stateless component in Wicket 1.5, by extending the component and giving the #StatelessComponent annotation,
I was trying to check the component being stateful/stateless with the StatelessChecker.
But i am not able to check, here is the code which i was trying .
#StatelessComponent
public class StatelessText extends TextField
//Client Class
StatelessText test = new StatelessText("test");
StatelessChecker sc = new StatelessChecker();
sc.onBeforeRender(test);
I dont see anything on console or any exceptions/errors.
Maybe i am not using the correct way, Can anybody please guide me here.
Appreciate the Help.

you have to register the StatelessChecker during the init of the WicketApplication.
/**
* #see org.apache.wicket.Application#init()
*/
#Override
public void init() {
super.init();
// might want to check if you're in dev mode or not...
getComponentPreOnBeforeRenderListeners().add(new StatelessChecker());
}

You dont need to explicitly call the Statelesschecker in your class. As Throsten said you need to add that in your WebApplications init and annotate your - class to be checked - as Statelesscomponent. If your Application is confidured to be in development mode in you web.xml you will get a runtime error when calling this page if it is Statefull.
Im not sure I understood what you are trying to do there. why are you holding an instance of your class in itself? are you trying to build a singleton? And what purpose does StatelessText has anyway? the Textfield in an usual form will be Stateless as long theres no explicitly added Ajax behaviour to it.