Dom4j解析xml

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mob604756e6cfe5 2021-08-13 14:09:00

文章标签 xml 子节点解析xml 编码格式读取文件 文章分类 代码人生

一、pom

<dependency>
    <groupId>dom4j</groupId>
    <artifactId>dom4j</artifactId>
    <version>1.6.1</version>
</dependency>

二、

//用list列表的方式来解析xml
public static void showStr() throws DocumentException {
    String str = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" + "\n" + "<books>\n" + "  <book id=\"005\">\n"
        + "    <title>Harry Potter</title>\n" + "    <author>J K. Rowling</author>\n" + "  </book>\n"
        + "  <book id=\"006\">\n" + "    <title>Learning XML</title>\n" + "    <author>Erik T. Ray</author>\n"
        + "  </book>\n" + "</books>";
    Document document = DocumentHelper.parseText(str);
    Element root = document.getRootElement();
    List<Element> childElements = root.elements();
    for (Element child : childElements) {
        //未知属性名情况下
        List<Attribute> attributeList = child.attributes();
        for (Attribute attr : attributeList) {
            System.out.println(attr.getName() + ": " + attr.getValue());
        }
        //已知属性名情况下
        //System.out.println("id: " + child.attributeValue("id"));

        //未知子元素名情况下
        List<Element> elementList = child.elements();
        for (Element ele : elementList) {
            System.out.println(ele.getName() + ": " + ele.getText());
        }
        System.out.println();
        // //已知子元素名的情况下
        // System.out.println("title" + child.elementText("title"));
        // System.out.println("author" + child.elementText("author"));
        // //这行是为了格式化美观而存在
        // System.out.println();
    }
}

//用list列表的方式来解析xml
public static void show() throws DocumentException {
    SAXReader reader = new SAXReader();
    File file = new File("D:\\aaaaaaaaaaa\\aa.xml");
    Document document = reader.read(file);
    Element root = document.getRootElement();
    List<Element> childElements = root.elements();
    for (Element child : childElements) {
        //未知属性名情况下
        List<Attribute> attributeList = child.attributes();
        for (Attribute attr : attributeList) {
            System.out.println(child.getName() + ":" + attr.getName() + ": " + attr.getValue());
        }
        //已知属性名情况下
        //System.out.println("id: " + child.attributeValue("id"));
        //未知子元素名情况下
        List<Element> elementList = child.elements();
        for (Element ele : elementList) {
            System.out.println(ele.getName() + ": " + ele.getText());
        }
        System.out.println();
        // //已知子元素名的情况下
        // System.out.println("title" + child.elementText("title"));
        // System.out.println("author" + child.elementText("author"));
        // //这行是为了格式化美观而存在
        // System.out.println();
    }
}

//创建一个xml
public static void createXML() throws IOException {
    Document doc = DocumentHelper.createDocument();
    //增加根节点
    Element books = doc.addElement("books");
    //增加子元素
    Element book1 = books.addElement("book");
    Element title1 = book1.addElement("title");
    Element author1 = book1.addElement("author");
    Element book2 = books.addElement("book");
    Element title2 = book2.addElement("title");
    Element author2 = book2.addElement("author");
    //为子节点添加属性
    book1.addAttribute("id", "003");
    //为元素添加内容
    title1.setText("Harry Potter");
    author1.setText("J K. Rowling");
    book2.addAttribute("id", "004");
    title2.setText("Learning XML");
    author2.setText("Erik T. Ray");
    //实例化输出格式对象
    OutputFormat format = OutputFormat.createPrettyPrint();
    //设置输出编码
    format.setEncoding("UTF-8");
    //创建需要写入的File对象
    File file = new File("D:" + File.separator + "books.xml");
    //生成XMLWriter对象，构造函数中的参数为需要输出的文件流和格式
    XMLWriter writer = new XMLWriter(new OutputStreamWriter(new FileOutputStream(file), "UTF-8"), format);
    //开始写入，write方法中包含上面创建的Document对象
    writer.write(doc);
    // 立即写入
    writer.flush();
    // 关闭操作
    writer.close();
}


xml事例

<?xml version="1.0" encoding="UTF-8"?>

<books>
　　<book id="003">
　　　　<title>Harry Potter</title>
　　　　<author>J K. Rowling</author>
　　</book>
　　<book id="004">
　　　　<title>Learning XML</title>
　　　　<author>Erik T. Ray</author>
　　</book>
</books>

　　xml工具类

/**
 *
 * @方法声明 读取文件
 * @param filePath 文件路径
 * @param encoding 读取编码格式
 * @return
 */
public static List readXmlFile(String filePath, String encoding) {
    try {
        if (encoding == null || "".equals(encoding)) {
            encoding = "UTF-8";
        }
        File file = new File(filePath);
        List list = new ArrayList<>();
        // 判断文件是否存在
        if (file.isFile() && file.exists()) {
            // 考虑到编码格式
            InputStreamReader read = new InputStreamReader(
                new FileInputStream(file), encoding);
            BufferedReader bufferedReader = new BufferedReader(read);
            String lineText = null;
            String allText = "";
            int i = 0;
            while ((lineText = bufferedReader.readLine()) != null) {
                if (i != 0) {
                    allText = allText + lineText;
                }
                i++;
            }
            list = XmlUtil.Xml2Map(allText);
            read.close();
            return list;
        } else {
            System.out.println("找不到指定的文件");
        }
    } catch (Exception e) {
        System.out.println("读取文件内容出错");
        e.printStackTrace();
    }
    return null;

}

/**
 *
 * @方法说明  节点解析
 * @param xml
 * @return
 */
public static List Xml2Map(String xml) {
    Document doc;
    try {
        doc = DocumentHelper.parseText(xml);
    } catch (DocumentException e1) {
        e1.printStackTrace();
        return null;
    }
    List list = new ArrayList<>();
    if (doc == null)
        return list;
    Element root = doc.getRootElement();
    list = Dom2Map(root);
    return list;
}
/**
 *
 * @方法声明 子节点解析（递归）
 * @param root
 * @return
 */
@SuppressWarnings("unchecked")
public static List<Map<String, Object>> Dom2Map(Element root) {
    List list = new ArrayList<>();
    //节点遍历
    for (Iterator<Element> iterator = root.elementIterator(); iterator
        .hasNext();) {
        Element e = (Element) iterator.next();
        Map<String, Object> map = new HashMap<String, Object>();
        String key = "";
        String value = "";
        Iterator attr = e.attributes().iterator();
        //节点属性遍历
        while (attr.hasNext()) {
            Attribute attribute = (Attribute) attr.next();
            key = attribute.getName();
            value = e.attribute(key).getValue();
            map.put(key, value);

        }
        // 判断有无子节点，有就递归解析子节点
        if (e.elements().size() > 0) {
            map.put("childnode", Dom2Map(e));
            list.add(map);
        } else {
            list.add(map);
        }
    }
    return list;
}