Error to get profile with external DB

[VU, Thi Thu Thuy]

Hello,
With shindig sample, i can get profile of john.doe for example following this 
link :
http://localhost:8080/social/rest/people/john.doe

But now, I want to use my own DB, so I created class spiGuiceOauth extends 
class SocialApiGuiceModule
protected void configure() {
            super.configure();

            bind(PersonService.class).to(PersonServiceImpl.class);
            bind(ActivityService.class).to(ActivityServiceImpl.class);
            bind(AppDataService.class).to((Class<? extends AppDataService>) 
AppDataServiceImpl.class);
            bind(OAuthDataStore.class).to(OAuthDataStoreImpl.class);
          }

          @Override
          protected Set<Object> getHandlers() {
            ImmutableSet.Builder<Object> handlers = ImmutableSet.builder();
            handlers.addAll(super.getHandlers());
            handlers.add(SampleContainerHandler.class);
            return handlers.build();
          }
And change file web.xml
org.apache.shindig.common.PropertiesModule:
      org.apache.shindig.gadgets.DefaultGuiceModule:
      spi.guiceModule.spiGuiceOauth:
      org.apache.shindig.gadgets.oauth.OAuthModule:
      org.apache.shindig.common.cache.ehcache.EhCacheModule

I tried to get profile of one person in my db for example :
http://localhost:8080/social/rest/people/ncox

but I don't understand why I until needs class JsonDbOpensocialService :(; It 
gave me this error:
No implementation for java.lang.String annotated with 
@com.google.inject.name.Named(value=shindig.canonical.json.db) was bound.
  while locating java.lang.String annotated with 
@com.google.inject.name.Named(value=shindig.canonical.json.db)
    for parameter 0 at 
org.apache.shindig.social.sample.spi.JsonDbOpensocialService.<init>(JsonDbOpensocialService.java:121)
  while locating org.apache.shindig.social.sample.spi.JsonDbOpensocialService
    for parameter 0 at 
org.apache.shindig.social.sample.service.SampleContainerHandler.<init>(SampleContainerHandler.java:47)
  while locating org.apache.shindig.social.sample.service.SampleContainerHandler

Could you give me some explanations, pls?
Thank you very much
Best regards.