public void CanSetOptional()
		{
			var mapdoc = new HbmMapping();
			var hbmJoin = new HbmJoin();
			var mapper = new JoinMapper(typeof(MyClass), "AA", hbmJoin, mapdoc);
			mapper.Optional(true);
			hbmJoin.optional.Should().Be.True();
		}
		public void CanSetOptional()
		{
			var mapdoc = new HbmMapping();
			var hbmJoin = new HbmJoin();
			var mapper = new JoinMapper(typeof(MyClass), "AA", hbmJoin, mapdoc);
			mapper.Optional(true);
			Assert.That(hbmJoin.optional, Is.True);
		}