I have a "strange" problem about Java generics.

First I list my code:

Service.class

package jse.generics.service;

public interface Service {

}

ServiceProvider.class

package jse.generics.service;

public interface ServiceProvider<T extends Service> {

    public T getService();
}

ServiceProviderRegistry.class

package jse.generics.service;

import java.util.HashMap;
import java.util.Map;

public class ServiceProviderRegistry<T extends Service> {

     private Map<Class<T>, ServiceProvider<T>> map = new HashMap<Class<T>, ServiceProvider<T>>();

     public void register(Class<T> clazz, ServiceProvider<T> provider) {
          map.put(clazz, provider);
     }
}

FooService.class

package jse.generics.service;

public class FooService implements Service {

}

FooServiceProvider.class

package jse.generics.service;

public class FooServiceProvider implements ServiceProvider<FooService> {

     @Override
     public FooService getService() {
          return new FooService();
     }

}

ServiceTest.class

package jse.generics.service;

public class ServiceTest {

     /**
     * @param args
     */
     public static void main(String[] args) {
          ServiceProviderRegistry<? extends Service> registry = new ServiceProviderRegistry<Service>();
          registry.register(FooService.class, new FooServiceProvider());
     }

}

In the ServiceTest class the compiler complaints that the registry.register method is not applicable for arguments passed to it.I really don't know why this happens. So I am looking forward to you guy's help to solve this problem.

java generics
Edit
Report