MEF and Workflow Services Integration

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Activities;
using System.ComponentModel.Composition;
using ModelLibrary;
using ContractsLibrary;
using BaseLibrary;

namespace WorkflowServiceLibrary.Activities
{

    public sealed class GetPendingOrders : CodeActivity<IEnumerable<Order>>
    {
        [Import]
        IOrderSubmissionService<Order> orderSubmissionService;

        protected override IEnumerable<Order> Execute(CodeActivityContext context)
        {
            context.GetExtension<MefWorkflowProvider>().Container.SatisfyImportsOnce(this);
            return orderSubmissionService.GetPendingOrders();
        }
    }
}