question: public void addNodesInDocOrder ( NodeIterator iterator , XPathContext support ) { if ( ! m_mutable ) throw new RuntimeException ( XSLMessages . createXPATHMessage ( XPATHErrorResources . ER_NODESET_NOT_MUTABLE , null ) ) ; Node node ; while ( null != ( node = iterator . nextNode ( ) ) ) { addNodeInDocOrder ( node , support ) ; } }
target:  Copy NodeList members into this nodelist, adding in document order.  If a node is null, don't add it.