Scott Hanselman's ComputerZen.com

Here's the deal:

1. It's expensive to make XmlSerializers (until .NET 2.0 when sgen.exe comes out and I can pre-created and compile Serializers.
2. I made an XmlSerializer Factory:
   

   public class XmlSerializerFactory
   {
      private XmlSerializerFactory(){}
      private static Hashtable serializers = new Hashtable();
      public static XmlSerializer GetSerializer(Type t)
      {
         XmlSerializer xs = null;
         lock(serializers.SyncRoot)
         {
             xs = serializers[t] as XmlSerializer;
             if(xs == null)
             { 
                xs = new XmlSerializer(t);
                serializers.Add(t,xs);
             }
         }
         return xs;
       }
   }

3. This Factory is thread safe (right?) BUT Are XmlSerializer instances ThreadSafe?  The MSDN Documentation gives the standard cop-out answer "They aren't explicitly Thread Safe..." (which means they weren't written to be, but also weren't written NOT to be)

So, to make sure I cover the case when someone is deserializing the same type of object using the SAME instance of a deserializer on multiple threads, I've been doing this:

XmlSerializer xs2 = XmlSerializerFactory.GetSerializer(typeof(MyNamedType));
lock(xs2)
{
   mynameInstance = (MyNamedType)xs2.Deserialize(someStringReader);
}

Is the lock{} needed? Am I being paranoid? Mr. Purdy?  Bueller?