Nhibernate: QuerySyntaxException: 'Class'没有映射。

I have the following class:

我有以下课程:

public class MyClass
{
    private List<long> _myList = new List<long>();

    public virtual string MyID { get; set; }

    public virtual string MyData
    {
        get
        {
            return SomeStaticClass.Serialize(_myList);
        }
        set
        {
            _myList = SomeStaticClass.Deserialize<List<long>>(value);
        }
    }

    public virtual List<long> MyList
    {
        get { return _myList; }
    }
}
public