java - 使用带有 int 值的 setAttribute 方法

Question

我试图将 int 值传递到 setAttribute 方法中，但收到错误消息

incompatible types int cannot be converted to string

如何解决这个问题而不弄乱我的代码？

我尝试将字符串解析为 int

public class DAOxml implements DAOInterface {

    private Document doc;

    @Override
    public void addWatch(DTOwatch dtoWatch) {
        doc = getDOMDocument();
        Element root = doc.getDocumentElement();

        Element watch = doc.createElement("watch");
        watch.setAttribute("ID", dtoWatch.id);

        Element imageText = doc.createElement("imageText");
        imageText.setTextContent(dtoWatch.imageText);

        Element imageUrl = doc.createElement("imageUrl");
        imageUrl.setTextContent(dtoWatch.imageUrl);

        Element likes = doc.createElement("likes");
        likes.setTextContent(String.valueOf(dtoWatch.likes));

        Element dislikes = doc.createElement("dislikes");
        dislikes.setTextContent(String.valueOf(dtoWatch.dislikes));

        watch.appendChild(imageText);
        watch.appendChild(imageUrl);
        watch.appendChild(likes);
        watch.appendChild(dislikes);
        root.appendChild(watch);
        writeToXML(doc);
    }

    @Override
    public void deleteWatch(String ID) {
        doc = getDOMDocument();
        Element root = doc.getDocumentElement();
        NodeList nodeList = root.getElementsByTagName("watch");
        String sokID;

        for (int i = 0; i < nodeList.getLength(); i++) {
            Element watch = (Element) nodeList.item(i);
            if (watch.hasAttributes()) {
                sokID = watch.getAttribute("ID");
                if (sokID.equalsIgnoreCase(ID)) {
                    root.removeChild(watch);
                    break;
                }
            }
        }
        writeToXML(doc);
    }

    @Override
    public void updateWatch(DTOwatch dtoWatch) {
        doc = getDOMDocument();
        Element root = doc.getDocumentElement();
        NodeList nodeList = root.getElementsByTagName("mobil");
        String sokID;

        for (int i = 0; i < nodeList.getLength(); i++) {
            Element watch = (Element) nodeList.item(i);
            if (watch.hasAttributes()) {
                sokID = watch.getAttribute("ID");
                if (sokID.equalsIgnoreCase(dtoWatch.id)) {
                    watch.getElementsByTagName("imageText").item(0).setTextContent(dtoWatch.imageText);
                    watch.getElementsByTagName("imageUrl").item(0).setTextContent(dtoWatch.imageUrl);
                    watch.getElementsByTagName("likes").item(0).setTextContent(String.valueOf(dtoWatch.likes));
                    watch.getElementsByTagName("dislikes").item(0).setTextContent(String.valueOf(dtoWatch.dislikes));
                    break;

                }
            }
        }
        writeToXML(doc);
    }

    @Override
    public List<DTOwatch> getWatch() {
        List<DTOwatch> watch = new ArrayList<>();
        doc = getDOMDocument();
        Element root = doc.getDocumentElement();
        NodeList nodeList = root.getElementsByTagName("watch");
        System.out.println(nodeList.getLength());

        for (int i = 0; i < nodeList.getLength(); i++) {
            Element watch = (Element) nodeList.item(i);

            DTOwatch dtoWatch = new DTOwatch();
            if (watch.hasAttributes()) {
                String ID = watch.getAttribute("ID");
                dtoWatch.id = id;
            }

            dtoWatch.imageText = watch.getElementsByTagName("imageText").item(0).getTextContent();
            dtoWatch.imageUrl = watch.getElementsByTagName("imageUrl;").item(0).getTextContent();
            dtoWatch.likes = Integer.parseInt(watch.getElementsByTagName("likes").item(0).getTextContent());
            dtoWatch.dislikes = Integer.parseInt(watch.getElementsByTagName("dislikes").item(0).getTextContent());
            watch.add(dtoWatch);
        }
        return watch;
    }

    private Document getDOMDocument() {

        try {
            DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();

            DocumentBuilder db = dbf.newDocumentBuilder();

            doc = db.parse(new File("watch.xml"));
        } catch (SAXException ex) {
            Logger.getLogger(DAOxml.class.getName() + ex.getMessage());
        } catch (IOException | ParserConfigurationException ex) {
            Logger.getLogger(DAOxml.class.getName() + ex.getMessage());
        }

        return doc;
    }

    private void writeToXML(Document doc) {

        try {
            TransformerFactory transformerFactory = TransformerFactory.newInstance();

            Transformer transformer = transformerFactory.newTransformer();

            transformer.setOutputProperty(OutputKeys.INDENT, "yes");
            transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "2");

            DOMSource source = new DOMSource(doc);

            StreamResult result = new StreamResult(new File("watch.xml"));

            transformer.transform(source, result);

            StreamResult consoleResult = new StreamResult(System.out);
            transformer.transform(source, consoleResult);
        } catch (TransformerException ex) {
            Logger.getLogger(DAOxml.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

我希望连接我的 XML 文件，并能够通过我用 javafx 制作的 gui 添加内容

Answer 1

根据Javadoc setAttribute() 方法接受两个参数:属性名称和属性值。两者都是字符串值。现在，这并不意味着 XML 模式将它们视为字符串。该架构可以将您的属性定义为 boolean 值、整数或其他值。但 Java 中的 setter 总是采用字符串。

因此，您需要首先使用 String.valueOf(...) 将 int 值转换为 String。

        watch.setAttribute("ID", String.valueOf(dtoWatch.id));

此外，您可能希望使用 JAXB 而不是直接在 Java 中操作 XML。 JAXB 将为您提供对 XML 结构的良好抽象，并且您将能够轻松地与 XML/Java 进行转换。如果你这样做，那么它会给你一个具有正确数据类型的 set... 方法。看看this tutorial开始吧。