Sample Repository Implementation

gett

There have been a number of postings advocating using a Repository to wrap EntityManager access, so I thought I'd toss out a simple sample implementation to generate discussion.  This is by no means production code, but should be basically functional.  

Some obvious opportunities for refinement would be introduction of an IRepository interface definition, and most likely replacing the Entity type constraint with your own entity base class.  

What else?  Any glaring problems?  Pros/cons?  Thoughts on generic class versus generic methods?

    public class Repository // base this on an IRepository interface definition
    {

        private MyEntityManager _defaultManager;

        public Repository()
        {
_defaultManager = MyEntityManager.DefaultManager;
        }

        public IEnumerable<T> FindAll<T>(Expression<Func<T, bool>> expression) 
where T : Entity
        {
            IEntityQuery<T> q = new EntityQuery<T>().Where(expression);
            return _defaultManager.ExecuteQuery(q);
        }

        public T Single<T>(Expression<Func<T, bool>> expression) where T : Entity
        {
            IEntityQuery<T> q = new EntityQuery<T>().Where(expression);
            return _defaultManager.ExecuteQuery(q).FirstOrDefault();
        }

        public T First<T>(Expression<Func<T, bool>> expression) where T : Entity
        {
            IEntityQuery<T> q = new EntityQuery<T>().Where(expression);
            return _defaultManager.ExecuteQuery(q).First();
        }

        public T Get<T>(Guid id) where T : Entity
        {
            return _defaultManager.FindEntity(new EntityKey(typeof(T), id)) as T;
        }

        public void MarkForDeletion<T>(T entity) where T : Entity
        {
            entity.EntityAspect.Delete();
        }

        public T Create<T>() where T : Entity
        {
            return _defaultManager.CreateEntity<T>();
        }

        public void SaveAll()
        {
            _defaultManager.SaveChanges();
        }
    }

Example usage:

Repository repository = new Repository();
IList foo = repository.FindAll<Contact>(c => c.Person.LastName == "Doe").ToList();

Looking forward to other's feedback.

Edited by chuckc - 16-May-2010 at 6:45pm