问题

// 有一列包含java.sql.Date，我想按升序将空值放在底部：

[![enter image description here][1]][1]

现在，它们最终出现在顶部。

followupCol.setCellFactory((TableColumn<DisabilityCase, Date> p) -> {
    TableCell<DisabilityCase, Date> cell = new TableCell<DisabilityCase, Date>() {
        @Override
        protected void updateItem(Date item, boolean empty) {
            super.updateItem(item, empty);
            if (item == null || empty) {
                setText(null);
            } else {
                if (!LocalDate.now().isBefore(item.toLocalDate())) {
                    setTextFill(Color.RED);
                } else {
                    setTextFill(Color.BLACK);
                }

                setText(new SimpleDateFormat(DATE_FORMAT).format(item));
            }
        }
    };

    return cell;
});

<details>
<summary>英文:</summary>

I have a column that contains java.sql.Date and I want it to put nulls at the bottom in ascending order:

[![enter image description here][1]][1]


Right now, they end up on top.


     followupCol.setCellFactory((TableColumn&lt;DisabilityCase, Date&gt; p) -&gt;
            {
                TableCell&lt;DisabilityCase, Date&gt; cell = new TableCell&lt;DisabilityCase, Date&gt;()
                {
                    @Override
                    protected void updateItem(Date item, boolean empty)
                    {
                        super.updateItem(item, empty);
                        if (item == null || empty)
                        {
                            setText(null);
                        } else
                        {
                            if (!LocalDate.now().isBefore(item.toLocalDate()))
                            {
                                setTextFill(Color.RED);
                            } else
                            {
                                setTextFill(Color.BLACK);
                            }
    
                            setText(new SimpleDateFormat(DATE_FORMAT).format(item));
                        }
                    }
    
                };
    

                return cell;
            });



  [1]: https://i.stack.imgur.com/aojM7.png

</details>


# 答案1
**得分**: 7

因为 `java.sql.Date` 已经实现了 `Comparable` 接口，所以你可以使用

```java
followupCol.setComparator(Comparator.nullsLast(Comparator.naturalOrder()));

followupCol.setComparator(Comparator.nullsLast(Comparator.naturalOrder()));