List of dates and values between the two dates using hashmap in javafx

@FXML
    private Map<Date,Integer> map=new HashMap<Date,Integer>();
    @FXML
    private ListView listview = new ListView();


            Date date1=new Date();
            Date date2=new Date();
            
            map.put(date1, 10);
            map.put(date2,20);
            
            listItems.add(map.get(date1));
            listItems.add(map.get(date2));
            
            for(Map.Entry<Date, Integer>entry: map.entrySet())
            {
                String d="Number of entries for "+entry.getKey().toString()+" = "+entry.getValue();
                listItems.add(d);
            }
             listview.setItems(listItems);
        }