TIdCommandHandlers = class(TIdOwnedCollection);

TIdCommandHandlers is a TOwnedCollection descendant that implements a collection of TIdCommandHandler items. TIdCommandHandlers publishes the Server property to identify the TIdTCPServer that owns the command handlers collection. 

TIdCommandHandlers is used to represent the CommandHandlers property in TIdTCPServer and descendant classes, and is accessed when a peer thread executes and command handlers are enabled. 

TIdCommandHandlers overrides methods in the ancestor class that Create the collection and establish the Server that owns the collection, and Add new collection items.