# File lib/rgen/serializer/xmi20_serializer.rb, line 9
        def serialize(rootElement)
                @referenceStrings = {}
                buildReferenceStrings(rootElement, "#/")
    addBuiltinReferenceStrings
                attrs = attributeValues(rootElement)
                attrs << ['xmi:version', "2.0"]
                attrs << ['xmlns:xmi', "http://www.omg.org/XMI"]
                attrs << ['xmlns:xsi', "http://www.w3.org/2001/XMLSchema-instance"]
                attrs << ['xmlns:ecore', "http://www.eclipse.org/emf/2002/Ecore" ]
                tag = "ecore:"+rootElement.class.ecore.name
                startTag(tag, attrs)
                writeComposites(rootElement)
                endTag(tag)
        end