@Override
  protected void loadAllSingletons() {
    if (!(xmlEntityContainer instanceof org.apache.olingo.client.api.edm.xml.v4.EntityContainer)) {
      throw new UnsupportedInV3Exception();
    }

    final List<Singleton> localSingletons =
        ((org.apache.olingo.client.api.edm.xml.v4.EntityContainer) xmlEntityContainer)
            .getSingletons();
    if (localSingletons != null) {
      for (Singleton singleton : localSingletons) {
        singletons.put(
            singleton.getName(),
            new EdmSingletonImpl(
                edm,
                this,
                singleton.getName(),
                new EdmTypeInfo.Builder()
                    .setTypeExpression(singleton.getEntityType())
                    .setDefaultNamespace(entityContainerName.getNamespace())
                    .build()
                    .getFullQualifiedName(),
                singleton));
      }
    }
  }