dom4j基本使用_xpath基本使用_junit测试

1. Java项目(Eclipse)结构

2. 项目下载(0积分)

dom4j_xpath_junitTest.zip

3. 代码

package org.foo.utils;

import java.io.FileWriter;
import java.io.IOException;
import java.net.URL;
import java.util.Iterator;
import java.util.List;

import org.dom4j.Attribute;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.dom4j.Node;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;
import org.junit.Test;


final public class XmlUtils {
	
	private static URL URL = XmlUtils.class.getClassLoader().getResource("configuration.xml");
	
	/** ---------------------------------- *\
			获取Document对象
	\*  ---------------------------------- */
	
	public static Document getDocument(URL url) throws DocumentException {
		// url = XmlUtils.class.getResource("configuration.xml");
		SAXReader reader = new SAXReader();                 
		return reader.read( url );
	}
	
	public static Document getDocument(String xmlString) throws DocumentException {
		/*
		xmlString =		"<configuration>                                                    " +
						"    <users>                                                        " +
						"        <user id='user_1' loginName='zhangsan' password='123'/>    " +
						"        <user id='user_2' loginName='lisi' password='456'>         " +
						"            <role name='admin'/>                                   " +
						"            <role name='programmer'/>                              " +
						"        </user>                                                    " +
						"    </users>                                                       " +
						"</configuration>                                                   " ;
		*/
		return DocumentHelper.parseText(xmlString); 
	}
	
	public static Document getDocument() throws DocumentException {
		// 空文档
		return DocumentHelper.createDocument();
	}
	
	
	
	
	/** ---------------------------------- *\
			将文档写入XML文件
	\*  ---------------------------------- */	
	
	// 普通写入(全英文,无缩进无换行)
	public static void write2Xml(Document document) throws IOException {
		XMLWriter writer = null;
		try {
			writer = new XMLWriter( new FileWriter(URL.getPath()) );
			writer.write(document);
		} finally {
			if (writer != null) {
				writer.close();
			}
		}
	}
	
	// 格式化写入(指定编码,缩进+换行)
	public static void write2XmlWithPrettyFormatAndEncoding(Document document, String encoding) throws IOException {
		XMLWriter writer = null;
		try {
			// format
			OutputFormat format = OutputFormat.createPrettyPrint(); 
			// characterSet, eg. UTF-8 GBK
			format.setEncoding(encoding);
			writer = new XMLWriter( new FileWriter(URL.getPath()), format );
			writer.write(document);
		} finally {
			if (writer != null) {
				writer.close();
			}
		}
	}
	
	
	/** ---------------------------------- *\
			字符串 <==> XML
	\*  ---------------------------------- */	
	
	public static Document xmlString2Document(String xmlString) throws DocumentException {
		if (xmlString == null) {
			xmlString =	"<configuration>                                                 " +
						"    <users>                                                     " +
						"        <user id='user_1' loginName='zhangsan' password='123'/> " +
						"        <user id='user_2' loginName='lisi' password='456'>      " +
						"            <role name='admin'/>                                " +
						"            <role name='programmer'/>                           " +
						"        </user>                                                 " +
						"    </users>                                                    " +
						"</configuration>                                                " ;
		}
		return DocumentHelper.parseText(xmlString); 
	}
	
	public static String document2XmlString(Document document) {
		return document.asXML();
	}
		
	
	/** ---------------------------------- *\
			节点对象操作
	\*  ---------------------------------- */
	
	// 1. 获取根节点
	@Test public void testOperationNode_1() throws Exception {
		Document document = getDocument( URL );
		Element rootElement = document.getRootElement();
		System.out.println("<" + rootElement.getName() + ">");
	}	
	
	// 2. 获取节点的<第一个>子节点
	@Test public void testOperationNode_2() throws Exception { 
		Document document = getDocument( URL );
		Element rootElement = document.getRootElement();
		Element firstChild = rootElement.element("users");
		System.out.println("<" + firstChild.getName() + ">");
	}
	
	// 3. 获取标签体内容( Text,CDATA and Entitynodes )
	@Test public void testOperationNode_3() throws Exception { 
		Document document = getDocument( URL );
		Element rootElement = document.getRootElement();
		String text = rootElement.getText();
		System.out.println("[" + text + "]");
	}
	
	// 4. 获取<所有的>子节点
	@Test public void testOperationNode_4() throws Exception { 
		Document document = getDocument( URL );
		Element rootElement = document.getRootElement();
		Element firstChild = rootElement.element("users");
		List<Element> children = firstChild.elements();
		for (Iterator it = children.iterator(); it.hasNext();) {      
			Element e = (Element) it.next();
			System.out.println( "<" + e.getName() + ">");
		}  
	}
	
	// 5. 遍历<子节点>
	@Test public void testOperationNode_5() throws Exception {
		Document document = getDocument( URL );
		Element rootElement = document.getRootElement();
		Element firstChild = rootElement.element("users");
		for (Iterator it = firstChild.elementIterator(); it.hasNext();) { 
			Element e = (Element) it.next();
			System.out.println( "<" + e.getName() + ">");
		}
	}
	
	// 6. 遍历<指定名称>的<子节点>
	@Test public void testOperationNode_6() throws Exception { 
		Document document = getDocument( URL );
		Element rootElement = document.getRootElement();
		for (Iterator it = rootElement.elementIterator("users"); it.hasNext();) { 
			Element e = (Element) it.next();
			System.out.println( "<" + e.getName() + ">");
		}
	}
	
	// 7. 添加<子节点>    注:操作节点后,需要将 document写入xml文件
	@Test public void testOperationNode_7() throws Exception { 
		Document document = getDocument( URL );
		Element rootElement = document.getRootElement();
		
		rootElement.addElement("addElment");
		
		System.out.println( document2XmlString(document) );
	}
	
	// 8. 给节点<添加文本>
	@Test public void testOperationNode_8() throws Exception { 
		Document document = getDocument( URL );
		Element rootElement = document.getRootElement();
		
		rootElement.addElement("addElment")
				   .setText("a new child");;
		
		System.out.println( document2XmlString(document) );
	}
	
	// 9. 删除<子节点>
	@Test public void testOperationNode_9() throws Exception { 
		Document document = getDocument( URL );
		Element rootElement = document.getRootElement();
		
		rootElement.remove( rootElement.element("users") );
		
		System.out.println( document2XmlString(document) );
	}
	
	// 10. 添加 CDATA节点
	@Test public void testOperationNode_10() throws Exception { 
		Document document = getDocument( URL );
		Element rootElement = document.getRootElement();
		
		rootElement.addCDATA("<c:if test=\"{wahh}\"></c:if>");
		
		System.out.println( document2XmlString(document) );
	}
	
	// 11. 根据<ID属性值>获取节点
	@Test public void testOperationNode_11() throws Exception { 
		Document document = getDocument( URL );
		// ID="user_1"
		Element element = document.elementByID("user_1");
		
		System.out.println( element.getName() );
	}
	
	
	/** ---------------------------------- *\
			节点对象的属性操作
	\*  ---------------------------------- */

	
	// 1. 获取某节点的<属性节点>
	@Test public void testOperationAttr_1() throws Exception { 
		Document document = getDocument( URL );
		Element element = document.elementByID("user_1");
		Attribute loginNameAttribute = element.attribute("loginName");
		System.out.println(loginNameAttribute);
	}
	
	// 2. 获取<属性节点>的值
	@Test public void testOperationAttr_2() throws Exception { 
		Document document = getDocument( URL );
		Element element = document.elementByID("user_1");
		Attribute loginNameAttribute = element.attribute("loginName");
		
		System.out.println(loginNameAttribute.getValue());
		System.out.println(loginNameAttribute.getText());
	}
	
	// 3. 删除<属性节点>
	@Test public void testOperationAttr_3() throws Exception { 
		Document document = getDocument( URL );
		Element element = document.elementByID("user_1");
		Attribute loginNameAttribute = element.attribute("loginName");
		
		element.remove(loginNameAttribute);
		
		System.out.println( document2XmlString(document) );
	}
	
	// 4. 遍历节点的所有属性
	@Test public void testOperationAttr_4() throws Exception { 
		Document document = getDocument( URL );
		Element element = document.elementByID("user_1");
		
		for (Iterator it = element.attributeIterator(); it.hasNext();){   
			Attribute attribute = (Attribute) it.next();
			String attributeName = attribute.getName();
			String attributeValue = attribute.getValue();
			System.out.println(attributeName + "=" + attributeValue);
		}
	}
	
	// 5. <添加/替换>属性节点
	@Test public void testOperationAttr_5() throws Exception { 
		Document document = getDocument( URL );
		Element element = document.elementByID("user_1");
		element.addAttribute("loginName", "zhang123"); // 替换
		element.addAttribute("newAttr", "wahh"); // 添加
		System.out.println(document2XmlString(document));
	}
	
	/** ---------------------------------- *\
				xpath-路径表达式
	\*  ---------------------------------- */
	
	/*
		/			从根节点选取; 从子节点中选
		//			从匹配选择的当前节点选择文档中的节点，而不考虑它们的位置; 从后代中选
		.			选取当前节点
		..			选取当前节点的父节点
		@			选取属性
	*/
	
	// 1. "/configuration/users/user"	从根节点开始,选取所有的<user>
	@Test public void testXpath_1() throws Exception { 
		Document document = getDocument( URL );
		
		String xpathExpression = "/configuration/users/user";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		for (Element element : nodeList) {
			System.out.println(element.attributeValue("ID"));
		}
	}
	
	// 2. "//user"	选取所有的<user>
	@Test public void testXpath_2() throws Exception { 
		Document document = getDocument( URL );
		
		String xpathExpression = "//user";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		for (Element element : nodeList) {
			System.out.println(element.attributeValue("ID"));
		}
	}
	
	// 3. "//users/user"	选取<users>的所有<user>子节点
	@Test public void testXpath_3() throws Exception { 
		Document document = getDocument( URL );
		
		String xpathExpression = "//users/user";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		for (Element element : nodeList) {
			System.out.println(element.attributeValue("ID"));
		}
	}
	
	// 4. "/configuration//user"	选取<configuration>的所有<user>后代节点
	@Test public void testXpath_4() throws Exception { 
		Document document = getDocument( URL );
		
		String xpathExpression = "/configuration//user";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		for (Element element : nodeList) {
			System.out.println(element.attributeValue("ID"));
		}
	}
	
	
	// 5. "//@loginName"	选取有属性名为 loginName 的属性节点
	@Test public void testXpath_5() throws Exception { 
		Document document = getDocument( URL );
		
		String xpathExpression = "//@loginName";
		
		List<Attribute> attributeList = document.selectNodes(xpathExpression);
		for (Attribute attribute : attributeList) {
			System.out.println(attribute.getValue());
		}
	}
	
	// 6. "//@password='123'"	是否存在 loginName='zhangsan' 的节点
	@Test public void testXpath_6() throws Exception { 
		Document document = getDocument( URL );
		
		String xpathExpression = "//@password='123'";
		
		List<Boolean> list = document.selectNodes(xpathExpression);
		
		for (Boolean isExist : list) {
			System.out.println(isExist);
		}
	}

	
	
	/** ---------------------------------- *\
			xpath-谓语（Predicates）
				谓语用来查找某个特定的节点或者包含某个指定的值的节点。
				谓语被嵌在方括号中。
	\*  ---------------------------------- */
	
	
	// 1. "//user[1]"	选取第一个<user>节点, 节点索引从1开始
	@Test public void testPredicates_1() throws Exception { 
		Document document = getDocument( URL );
		
		String xpathExpression = "//user[1]";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		
		for (Element element : nodeList) {
			System.out.println(element.attributeValue("ID"));
		}
	}
	
	// 2. "//user[last()]"	选取最后<user>节点
	@Test public void testPredicates_2() throws Exception { 
		Document document = getDocument( URL );
		
		String xpathExpression = "//user[last()]";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		
		for (Element element : nodeList) {
			System.out.println(element.attributeValue("ID"));
		}
	}
	
	// 3. "//user[last()-1]"	选倒数第二个<user>节点
	@Test public void testPredicates_3() throws Exception { 
		Document document = getDocument( URL );
		
		String xpathExpression = "//user[last()-1]";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		
		for (Element element : nodeList) {
			System.out.println(element.attributeValue("ID"));
		}
	}
	
	// 4. "//user[position()<3]"	选前两个<user>节点
	@Test public void testPredicates_4() throws Exception { 
		Document document = getDocument( URL );
		
		String xpathExpression = "//user[position()<3]";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		
		for (Element element : nodeList) {
			System.out.println(element.attributeValue("ID"));
		}
	}
	
	// 5. "//user[@loginName]"	选有loginName属性的<user>节点
	@Test public void testPredicates_5() throws Exception { 
		Document document = getDocument( URL );
		
		String xpathExpression = "//user[@loginName]";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		
		for (Element element : nodeList) {
			System.out.println(element.attributeValue("ID"));
		}
	}
	
	// 6. "//user[@loginName='zhangsan']"	选 loginName属性=zhangsan 的<user>节点
	@Test public void testPredicates_6() throws Exception { 
		Document document = getDocument( URL );
		
		String xpathExpression = "//user[@loginName='zhangsan']";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		
		for (Element element : nodeList) {
			System.out.println(element.attributeValue("ID"));
		}
	}
	
	
	/** ---------------------------------- *\
				通配符
	\*  ---------------------------------- */
	
	/*
	 		*		匹配任何元素节点
	 		@* 		匹配任何属性节点
	 		node() 	匹配任何类型节点
	 */
	
	// 1. "//products/*"	products的所有子节点(元素节点)
	@Test public void testWildcard_1() throws Exception {
		Document document = getDocument( URL );
		
		String xpathExpression = "//products/*";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		
		for (Element element : nodeList) {
			System.out.println(element.attributeValue("name"));
		}
	}
	
	// 2. "//*"	所有元素节点
	@Test public void testWildcard_2() throws Exception {
		Document document = getDocument( URL );
		
		String xpathExpression = "//*";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		
		for (Element element : nodeList) {
			System.out.println(element.getName());
		}
	}
	
	// 3. "//product[@*]"	带有属性的<product>节点
	@Test public void testWildcard_3() throws Exception {
		Document document = getDocument( URL );
		
		String xpathExpression = "//product[@*]";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		
		for (Element element : nodeList) {
			System.out.println(element.getName());
		}
	}
	
	// 4. "//products/node()"	<products>所有节点(元素节点,文本节点)
	@Test public void testWildcard_4() throws Exception {
		Document document = getDocument( URL );
		
		String xpathExpression = "//products/node()";
		
		List<Node> nodeList = document.selectNodes(xpathExpression);
		
		for (Node node : nodeList) {
			short nodeType = node.getNodeType();
			switch (nodeType) {
				case Node.ELEMENT_NODE:
					System.out.println("<" + node.getName() + ">");
					break;
				case Node.ATTRIBUTE_NODE:
					System.out.println(node.getName() + "=" + node.getText());
					break;
				case Node.TEXT_NODE:
					System.out.println("[" + node.getText() + "]");
					break;
			}
		}
	}
	
	/** ---------------------------------- *\
				|  路径 连接, 求多个路径的并集
	\*  ---------------------------------- */	
	
	@Test public void testPathUnion() throws Exception {
		Document document = getDocument( URL );
		
		String xpathExpression = "//product[@name='Java']  |  //user[@ID='user_3']";
		
		List<Element> nodeList = document.selectNodes(xpathExpression);
		
		for (Element element : nodeList) {
			String nodeName = element.getName();
			System.out.print("<" + nodeName);
			for (Object attr : element.attributes()) {
				Attribute attribute = (Attribute) attr;
				String attributeName = attribute.getName();
				String attributeValue = attribute.getValue();
				
				System.out.print(" " + attributeName + "=\"" + attributeValue + "\"");
			}
			System.out.println(">");
		}
			
	}
	
}

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
        
	<users>
	
		<user ID="user_1" loginName="zhangsan" password="123"/>
		
		<user ID="user_2" loginName="lisi" password="123">
			<role name="admin"/>
			<role name="programmer"/>
		</user>
		
		<user ID="user_3" loginName="zhangsan" password="123"/>
		
	</users>
	
	<products>
		<product name="Java" price="99.99"/>
		<product name="JavaScript" price="77.99"/>
		<product name="C" price="66.99"/>
		<product name="C++" price="55.99"/>
		<product name="C#" price="44.99"/>
		<product/>
	</products>
    
</configuration>