4

我有一个名为 Entity 的基类：

public class Entity
{
    public int Id {get;set;}
}

假设我有一个名为 Customer 的类：

public class Customer : Entity
{
    public string Name {get;set;}
}

现在，通过 NHibernate 3.3.1 中的代码使用基于约定的映射，我尝试以下操作：

public static class DataHelper
{
    private static HbmMapping GetMappings()
    {
        var mapper = new CustomModelMapper(typeof(Entity));           

        return mapper.CompileMappingFor(
            typeof(DataHelper).Assembly.GetExportedTypes()
                .Where(x => x.IsSubclassOf(typeof(Entity))));
    }
}

当我尝试运行我的应用程序时，我收到错误“无法扩展未映射的类：实体”。我不想映射 Entity 类——它只是一个用于继承一些公共属性的基类。如何告诉 NHibernate 忽略未映射的类？作为参考，下面列出了我的 CustomModelMapper 类。

下面列出了我的 CustomModelMapper 类的代码以供参考 

internal class CustomModelMapper : ConventionModelMapper
{
    private const int DEFAULT_STRING_LENGTH = 100;
    private Type baseType;

    public CustomModelMapper(Type baseType)
    {
        this.baseType = baseType;
    }

    public CustomModelMapper()
    {
        SetupInspectors();
    }

    protected override void AppendDefaultEvents()
    {
        base.AppendDefaultEvents();
        BeforeMapClass += OnBeforeMapClass;
        BeforeMapProperty += OnBeforeMapProperty;
        BeforeMapManyToOne += OnBeforeMapManyToOne;
        BeforeMapBag += OnBeforeMapBag;
        BeforeMapList += OnBeforeMapList;
        BeforeMapSet += OnBeforeMapSet;
    }

    protected void OnBeforeMapClass(IModelInspector modelInspector, Type type, IClassAttributesMapper classCustomizer)
    {
        classCustomizer.Id(type.GetProperty("Id"), m => m.Generator(Generators.Native));
    }

    protected void OnBeforeMapProperty(IModelInspector modelInspector, PropertyPath member, IPropertyMapper propertyCustomizer)
    {
        if (member.LocalMember.GetPropertyOrFieldType().IsEnum)
        {
            var type = member.LocalMember.GetPropertyOrFieldType();
            var genericType = typeof(EnumStringType<>).MakeGenericType(type);
            propertyCustomizer.Type(genericType, null);
        }

        if (member.LocalMember.GetPropertyOrFieldType() == typeof(string))
            propertyCustomizer.Length(DEFAULT_STRING_LENGTH);
    }

    protected void OnBeforeMapManyToOne(IModelInspector modelInspector, PropertyPath member, IManyToOneMapper propertyCustomizer)
    {
        propertyCustomizer.Cascade(Cascade.All);
        propertyCustomizer.Fetch(FetchKind.Join);
        propertyCustomizer.Lazy(LazyRelation.NoLazy);

        propertyCustomizer.Index(string.Format("IX{0}{1}",
            member.GetContainerEntity(modelInspector).Name,
            member.LocalMember.Name));
    }

    protected void OnBeforeMapBag(IModelInspector modelInspector, PropertyPath member, IBagPropertiesMapper propertyCustomizer)
    {
        propertyCustomizer.Cascade(Cascade.All);
        propertyCustomizer.Lazy(CollectionLazy.Extra);
        propertyCustomizer.Fetch(CollectionFetchMode.Subselect);
    }

    protected void OnBeforeMapList(IModelInspector modelInspector, PropertyPath member, IListPropertiesMapper propertyCustomizer)
    {
        propertyCustomizer.Cascade(Cascade.All);
        propertyCustomizer.Lazy(CollectionLazy.Extra);
        propertyCustomizer.Fetch(CollectionFetchMode.Subselect);
    }

    protected void OnBeforeMapSet(IModelInspector modelInspector, PropertyPath member, ISetPropertiesMapper propertyCustomizer)
    {
        propertyCustomizer.Cascade(Cascade.All);
        propertyCustomizer.Lazy(CollectionLazy.Extra);
        propertyCustomizer.Fetch(CollectionFetchMode.Subselect);
    }

    protected void SetupInspectors()
    {
        IsRootEntity((type, declared) =>
        {
            return baseType.Equals(type.BaseType);
        });

        IsEntity((type, declared) =>
        {
            return baseType.IsAssignableFrom(type) && !type.IsInterface;
        });

        IsVersion((member, declared) =>
        {
            return
                member.Name == "Version" &&
                member.MemberType == MemberTypes.Property &&
                member.GetPropertyOrFieldType() == typeof(int);
        });


        IsBag((member, declared) =>
        {
            if (member.GetPropertyOrFieldType().IsGenericType)
                return IsGenericType(member, typeof(ICollection<>));

            return false;
        });

        IsList((member, declared) =>
        {
            if (member.GetPropertyOrFieldType().IsGenericType)
                return IsGenericType(member, typeof(IList<>));

            return false;
        });

        IsSet((member, declared) =>
        {
            if (member.GetPropertyOrFieldType().IsGenericType)
                return IsGenericType(member, typeof(ICG.ISet<>));

            return false;
        });
    }

    protected static bool IsGenericType(MemberInfo member, Type targetType)
    {
        var type = member.GetPropertyOrFieldType();
        var generics = type.GetGenericInterfaceTypeDefinitions();
        return generics.Contains(targetType);
    }
}
4

1 回答 1

3

问题可能与您的IsEntity约定有关。目前，它将为Entity类本身返回 true。只需添加另一个检查：

IsEntity((type, declared) =>
{
    return baseType.IsAssignableFrom(type) && !type.IsInterface &&
           type != typeof(Entity); // <- skip Entity class
});

编辑

此外，您的CustomModelMapper类中有两个构造函数。其中一个接受基本类型，另一个是 default 并调用SetupInspectors(). 正如我所看到的，您的默认构造函数将永远不会被调用，因为您正在调用接受基类型的构造函数，并且它不会调用默认构造函数......

这样做的结果是......你的SetupInspectors()方法也永远不会被调用。

于 2012-07-09T21:07:49.467 回答