CollectionJoinWalker.cs

using System.Collections.Generic;
using NHibernate.Engine;
using NHibernate.SqlCommand;
using NHibernate.Util;

namespace NHibernate.Loader.Collection
{
	/// <summary>
	/// Superclass of walkers for collection initializers
	/// <seealso cref="CollectionLoader" />
	/// <seealso cref="OneToManyJoinWalker" />
	/// <seealso cref="BasicCollectionJoinWalker" />
	/// </summary>
	public abstract class CollectionJoinWalker : JoinWalker
	{
		public CollectionJoinWalker(ISessionFactoryImplementor factory, IDictionary<string, IFilter> enabledFilters)
			: base(factory, enabledFilters)
		{
		}

		protected SqlStringBuilder WhereString(string alias, string[] columnNames, SqlString subselect,
		                                       int batchSize)
		{
			if (subselect == null)
			{
				return WhereString(alias, columnNames, batchSize);
			}
			else
			{
				SqlStringBuilder buf = new SqlStringBuilder();

				if (columnNames.Length > 1)
					buf.Add("(");

				buf.Add(StringHelper.Join(StringHelper.CommaSpace, StringHelper.Qualify(alias, columnNames)));
				
				if (columnNames.Length > 1)
					buf.Add(")");

				buf.Add(" in ")
					.Add("(")
					.Add(subselect)
					.Add(")");
				return buf;
			}
		}
	}
}