public Object getValueAt(int rowIndex, int columnIndex){
    	//ڼУǶеڼ̶߳û
    	UserInfo  user=users.get(rowIndex);
    	if(columnIndex==0){
    		return user.getJkNum();
    	}else if(columnIndex==1){
        		return user.getNikeName();
    	}else{ return "error"; }
    }