isInDocumentOrder = false;
	public void sort() {		//		long start = System.currentTimeMillis();		if (isSorted)			return;		Part part;		size = 0;		for (Iterator i = map.valueIterator(); i.hasNext(); ) {			part = (Part) i.next();			part.sort();			size += part.removeDuplicates();		}		isSorted = true;		//		System.out.println("sort took " + (System.currentTimeMillis() -		// start) + "ms.");	}