Lazy mapping schema loading

Author: bahusoid

src/NHibernate/Cfg/XmlSchemas.cs

@@ -11,7 +11,11 @@ internal class XmlSchemas
 		private const string MappingSchemaResource = "NHibernate.nhibernate-mapping.xsd";
 
 		private static readonly XmlSchemaSet ConfigSchemaSet = ReadXmlSchemaFromEmbeddedResource(CfgSchemaResource);
-		private static readonly XmlSchemaSet MappingSchemaSet = ReadXmlSchemaFromEmbeddedResource(MappingSchemaResource);
+
+		private static class MappingSchemaHolder
+		{
+			public static readonly XmlSchemaSet MappingSchemaSet = ReadXmlSchemaFromEmbeddedResource(MappingSchemaResource);
+		}
 
 		public XmlReaderSettings CreateConfigReaderSettings()
 		{
@@ -23,7 +27,7 @@ public XmlReaderSettings CreateConfigReaderSettings()
 
 		public XmlReaderSettings CreateMappingReaderSettings()
 		{
-			return CreateXmlReaderSettings(MappingSchemaSet);
+			return CreateXmlReaderSettings(MappingSchemaHolder.MappingSchemaSet);
 		}
 
 		private static XmlSchemaSet ReadXmlSchemaFromEmbeddedResource(string resourceName)
@@ -50,4 +54,4 @@ private static void ConfigSettingsValidationEventHandler(object sender, Validati
 			throw new HibernateConfigException("An exception occurred parsing configuration :" + e.Message, e.Exception);
 		}
 	}
-}
+}