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  • dom4j

    要使用dom4j读写XML文档,需要先下载dom4j包,dom4j官方网站在 http://www.dom4j.org/
    目前最新dom4j包下载地址:http://nchc.dl.sourceforge.net/sourceforge/dom4j/dom4j-1.6.1.zip

    解开后有两个包,仅操作XML文档的话把dom4j-1.6.1.jar加入工程就可以了,如果需要使用XPath的话还需要加入包jaxen-1.1-beta-7.jar

    一.Document对象相关

    1.读取XML文件,获得document对象.
                SAXReader reader = new SAXReader();
                Document  document = reader.read(new File("input.xml"));

    2.解析XML形式的文本,得到document对象.
                String text = "";
                Document document = DocumentHelper.parseText(text);
    3.主动创建document对象.
                Document document = DocumentHelper.createDocument();
                Element root = document.addElement("members");// 创建根节点

    二.节点相关

    1.获取文档的根节点.
    Element rootElm = document.getRootElement();
    2.取得某节点的单个子节点.
    Element memberElm=root.element("member");// "member"是节点名
    3.取得节点的文字
    String text=memberElm.getText();
    也可以用:
    String text=root.elementText("name");这个是取得根节点下的name字节点的文字.

    4.取得某节点下名为"member"的所有字节点并进行遍历.
    List nodes = rootElm.elements("member");

    for (Iterator it = nodes.iterator(); it.hasNext();) {
       Element elm = (Element) it.next();
       // 
    }
    5.对某节点下的所有子节点进行遍历.

               for(Iterator it=root.elementIterator();it.hasNext();){
                    Element element = (Element) it.next();
                    // 
                }


    6.在某节点下添加子节点.
    Element ageElm = newMemberElm.addElement("age");
    7.设置节点文字.
    ageElm.setText("29");
    8.删除某节点.
    parentElm.remove(childElm);// childElm是待删除的节点,parentElm是其父节点
    三.属性相关.
    1.取得某节点下的某属性
                Element root=document.getRootElement();    
                Attribute attribute=root.attribute("size");// 属性名name
    2.取得属性的文字
                String text=attribute.getText();
    也可以用:
    String text2=root.element("name").attributeValue("firstname");这个是取得根节点下name字节点的属性firstname的值.

    3.遍历某节点的所有属性
                Element root=document.getRootElement();    
                for(Iterator it=root.attributeIterator();it.hasNext();){
                    Attribute attribute = (Attribute) it.next();
                    String text=attribute.getText();
                    System.out.println(text);
                }
    4.设置某节点的属性和文字.
    newMemberElm.addAttribute("name", "sitinspring");
    5.设置属性的文字
                Attribute attribute=root.attribute("name");
                attribute.setText("sitinspring");
    6.删除某属性
                Attribute attribute=root.attribute("size");// 属性名name
                root.remove(attribute);

    四.将文档写入XML文件.
    1.文档中全为英文,不设置编码,直接写入的形式.
    XMLWriter writer = new XMLWriter(new FileWriter("output.xml"));
    writer.write(document);
    writer.close();
    2.文档中含有中文,设置编码格式写入的形式.
                OutputFormat format = OutputFormat.createPrettyPrint();
                format.setEncoding("GBK");    // 指定XML编码        
                XMLWriter writer = new XMLWriter(new FileWriter("output.xml"),format);
                
                writer.write(document);
                writer.close();
    五.字符串与XML的转换
    1.将字符串转化为XML
    String text = " sitinspring ";
    Document document = DocumentHelper.parseText(text);
    2.将文档或节点的XML转化为字符串.

    SAXReader reader = new SAXReader();
                Document  document = reader.read(new File("input.xml"));            
                Element root=document.getRootElement();                
                String docXmlText=document.asXML();
                String rootXmlText=root.asXML();
                Element memberElm=root.element("member");
                String memberXmlText=memberElm.asXML();
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  • 原文地址:https://www.cnblogs.com/yinghao/p/4794012.html
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