HbmMapKey.cs

using System.Collections.Generic;
using System.Linq;
using System.Xml.Serialization;
using NHibernate.Util;

namespace NHibernate.Cfg.MappingSchema
{
	public partial class HbmMapKey: IColumnsMapping, ITypeMapping
	{
		#region Implementation of IColumnsMapping

		[XmlIgnore]
		public IEnumerable<HbmColumn> Columns
		{
			get { return !ArrayHelper.IsNullOrEmpty(Items) ? Items.OfType<HbmColumn>() : AsColumns(); }
		}

		#endregion

		private IEnumerable<HbmColumn> AsColumns()
		{
			if (string.IsNullOrEmpty(column))
			{
				yield break;
			}
			else
			{
				yield return new HbmColumn
				{
					name = column,
					length = length,
				};
			}
		}

		#region Implementation of IFormulasMapping

		[XmlIgnore]
		public IEnumerable<HbmFormula> Formulas
		{
			get { return !ArrayHelper.IsNullOrEmpty(Items) ? Items.OfType<HbmFormula>() : AsFormulas(); }
		}

		private IEnumerable<HbmFormula> AsFormulas()
		{
			if (string.IsNullOrEmpty(formula))
			{
				yield break;
			}
			else
			{
				yield return new HbmFormula { Text = new[] { formula } };
			}
		}

		#endregion

		#region Implementation of ITypeMapping

		public HbmType Type
		{
			get { return string.IsNullOrEmpty(type) ? null : new HbmType { name = type }; }
		}

		#endregion

		/// <summary>
		/// Columns and Formulas, in declared order
		/// </summary>
		[XmlIgnore]
		public IEnumerable<object> ColumnsAndFormulas
		{
			get
			{
				if (!ArrayHelper.IsNullOrEmpty(Items) && (!string.IsNullOrEmpty(column) || !string.IsNullOrEmpty(formula)))
					throw new MappingException(
						"On a map-key: specifying columns or formulas with both attributes and sub-elements is " +
						"invalid. Please use only sub-elements, or only one of them as attribute");
				if (!string.IsNullOrEmpty(column) && !string.IsNullOrEmpty(formula))
					throw new MappingException(
						"On a map-key: specifying both column and formula attributes is invalid. Please specify " +
						"only one of them, or use sub-elements");
				return !ArrayHelper.IsNullOrEmpty(Items) ? Items : AsColumns().Cast<object>().Concat(AsFormulas());
			}
		}
	}
}