protected boolean iterate_precedingNS(String URL, String ln)
protected boolean iterate_precedingNS(String URL, int dp, String ln)
	protected boolean iterate_precedingNS(String URL, String ln)	throws NavException {		int index = getCurrentIndex() - 1;		int t,d;		//int size = vtdBuffer.size();		while (index >=0) {			if (isElementOrDocument(index)) {				int depth = getTokenDepth(index);				context[0] = depth;				//context[depth]=index;				if (depth>0){					context[depth] = index;					t = index -1;					for (int i=depth-1;i>0;i--){						if (context[i]>index){							while(t>0){								d = getTokenDepth(t);								if ( d == i && isElement(t)){									context[i] = t;									break;								}								t--;							}													}else							break;					}				}				//dumpContext();				if (matchElementNS(URL,ln)) {										resolveLC();					return true;				}			} else				index--;		}		return false;		}