public int compare(Object o1,Object o2) {
	    	InveList result1 = (InveList)o1;
	    	InveList result2 = (InveList)o2;
	    	if(result1.getTf() < result2.getTf())
	    		return 1;
	    	else if (result1.getTf() > result2.getTf())
	    		return -1;
	    	else if (result1.getTf() == result2.getTf()) {
	    		if (result1.getDocID() < result2.getDocID())
	        	   return 1;
	    	}
	    	return -1;
	    }