XML操作之dom4j

依赖

<dependency>
    <groupId>dom4j</groupId>
    <artifactId>dom4j</artifactId>
    <version>1.6.1</version>
</dependency>
<dependency>
    <groupId>jaxen</groupId>
    <artifactId>jaxen</artifactId>
    <version>1.2.0</version>
</dependency>

dom4j:解析，生成
jaxen:查找节点

读取

XML样例

<root>
	<head>
		<accessToken>token</accessToken>
	</head>
	<body>
		<request>
			<param id='123' age='18'>张三</param>
			<param id='456' age='20'>李四</param>
		</request>
	</body>
</root>

读取xml文件

Document document = new SAXReader().read(filePath);
Element rootElement = document.getRootElement();

读取xml字符串

Document document = DocumentHelper.parseText(xmlStr);
Element rootElement = document.getRootElement();

解析

解析属性

String attributeKey = rootElement.attributeValue("attributeKey");

解析下级节点

Element ele = rootElement.element("elementName")

迭代下级节点(多个)

Iterator<Element> rootIter = root.elementIterator();	
while (rootIter.hasNext()) {
    Element ele = rootIter.next();
    System.out.println(ele.getName());
}

查找

单节点：String accessToken = rootElement.selectSingleNode("/root/head/accessToken").getStringValue();   
多节点：List param = root.selectNodes("/root/body/request/param");

生成

生成xml文档

// 创建一个Document实例
Document document = DocumentHelper.createDocument();
Element rootEle = document.addElement("root");

Element headEle = rootEle.addElement("head");
headEle.addElement("accessToken").addText("token");

Element bodyEle = rootEle.addElement("body");
Element requestEle =  bodyEle.addElement("request");
requestEle.addElement("param").addAttribute("id","123").addAttribute("age","18").addText("张三");
requestEle.addElement("param").addAttribute("id","124").addAttribute("age","20").addText("李四");

输出xml字符串

String str = document.asXML();

输出xml文件

展开格式：OutputFormat format = OutputFormat.createPrettyPrint();
压缩格式：OutputFormat format = OutputFormat.createCompactFormat();

// 自定义xml样式
OutputFormat format = new OutputFormat();
format.setEncoding("UTF-8");
format.setNewLineAfterDeclaration(false); // 放置xml文件中第二行为空白行
// 输出xml文件
XMLWriter writer = new XMLWriter(new FileOutputStream(filePath), format);
writer.write(document);