解析xml

package gz.itcast.a_dom4j_read;import java.io.File;import org.dom4j.Document;import org.dom4j.DocumentException;import org.dom4j.io.SAXReader;/** * 第一个Dom4j读取xml文档的例子 * @author APPle * */public class Demo1 {public static void main(String[] args) {try {//1.创建一个xml解析器对象SAXReader reader = new SAXReader();//2.读取xml文档，返回Document对象Document doc = reader.read(new File("./src/contact.xml"));System.out.println(doc);} catch (DocumentException e) {e.printStackTrace();throw new RuntimeException(e);}}}

package gz.itcast.a_dom4j_read;import java.io.File;import java.util.Iterator;import java.util.List;import org.dom4j.Attribute;import org.dom4j.Document;import org.dom4j.Element;import org.dom4j.Node;import org.dom4j.io.SAXReader;import org.junit.Test;/** * 第二个dom4j读取xml文件内容 * 节点 * 标签 * 属性 * 文本 * @author APPle * */public class Demo2 {/** * 得到节点信息 */@Testpublic void test1() throws Exception{//1.读取xml文档，返回Document对象SAXReader reader = new SAXReader();Document doc = reader.read(new File("./src/contact.xml"));//2.nodeIterator: 得到当前节点下的所有子节点对象(不包含孙以下的节点)Iterator<Node> it = doc.nodeIterator();while(it.hasNext()){//判断是否有下一个元素Node node = it.next();//取出元素String name = node.getName();//得到节点名称//System.out.println(name);//System.out.println(node.getClass());//继续取出其下面的子节点//只有标签节点才有子节点//判断当前节点是否是标签节点if(node instanceof Element){Element elem = (Element)node;Iterator<Node> it2 = elem.nodeIterator();while(it2.hasNext()){Node n2 = it2.next();System.out.println(n2.getName());}}}}/** * 遍历xml文档的所有节点 * @throws Exception */@Testpublic void test2() throws Exception{//1.读取xml文档，返回Document对象SAXReader reader = new SAXReader();Document doc = reader.read(new File("./src/contact.xml"));//得到根标签Element rooElem = doc.getRootElement();getChildNodes(rooElem);}/** * 获取 传入的标签下的所有子节点 * @param elem */private void getChildNodes(Element elem){System.out.println(elem.getName());//得到子节点Iterator<Node> it = elem.nodeIterator();while(it.hasNext()){Node node = it.next();//1.判断是否是标签节点if(node instanceof Element){Element el = (Element)node;//递归getChildNodes(el);}};}/** * 获取标签 */@Testpublic void test3() throws Exception{//1.读取xml文档，返回Document对象SAXReader reader = new SAXReader();Document doc = reader.read(new File("./src/contact.xml"));//2.得到根标签Element  rootElem = doc.getRootElement();//得到标签名称String name = rootElem.getName();System.out.println(name);//3.得到当前标签下指定名称的第一个子标签/*Element contactElem = rootElem.element("contact");System.out.println(contactElem.getName());*///4.得到当前标签下指定名称的所有子标签/*Iterator<Element> it = rootElem.elementIterator("contact");while(it.hasNext()){Element elem = it.next();System.out.println(elem.getName());}*///5.得到当前标签下的的所有子标签List<Element> list = rootElem.elements();//遍历List的方法//1)传统for循环  2）增强for循环 3）迭代器/*for(int i=0;i<list.size();i++){Element e = list.get(i);System.out.println(e.getName());}*//*for(Element e:list){System.out.println(e.getName());}*//*Iterator<Element> it = list.iterator(); //ctrl+2 松开 lwhile(it.hasNext()){Element elem = it.next();System.out.println(elem.getName());}*///获取更深层次的标签(方法只能一层层地获取)Element nameElem = doc.getRootElement().element("contact").element("name");System.out.println(nameElem.getName());}/** * 获取属性 */@Testpublic void test4() throws Exception{//1.读取xml文档，返回Document对象SAXReader reader = new SAXReader();Document doc = reader.read(new File("./src/contact.xml"));//获取属性：（先获的属性所在的标签对象，然后才能获取属性）//1.得到标签对象Element contactElem = doc.getRootElement().element("contact");//2.得到属性//2.1  得到指定名称的属性值/*String idValue = contactElem.attributeValue("id");System.out.println(idValue);*///2.2 得到指定属性名称的属性对象/*Attribute idAttr = contactElem.attribute("id");//getName： 属性名称    getValue：属性值System.out.println(idAttr.getName() +"=" + idAttr.getValue());*///2.3 得到所有属性对象,返回LIst集合/*List<Attribute> list = contactElem.attributes();//遍历属性for (Attribute attr : list) {System.out.println(attr.getName()+"="+attr.getValue());}*///2.4 得到所有属性对象，返回迭代器Iterator<Attribute> it = contactElem.attributeIterator();while(it.hasNext()){Attribute attr = it.next();System.out.println(attr.getName()+"="+attr.getValue());}}/** * 获取文本 */@Testpublic void test5() throws Exception{//1.读取xml文档，返回Document对象SAXReader reader = new SAXReader();Document doc = reader.read(new File("./src/contact.xml"));/** * 注意: 空格和换行也是xml的内容 */String content = doc.getRootElement().getText();System.out.println(content);//获取文本（先获取标签，再获取标签上的文本）Element nameELem = doc.getRootElement().element("contact").element("name");//1. 得到文本String text = nameELem.getText();System.out.println(text);//2. 得到指定子标签名的文本内容String text2 = doc.getRootElement().element("contact").elementText("phone");System.out.println(text2);}}

package gz.itcast.a_dom4j_read;import java.io.File;import java.util.Iterator;import java.util.List;import org.dom4j.Attribute;import org.dom4j.Document;import org.dom4j.Element;import org.dom4j.Node;import org.dom4j.Text;import org.dom4j.io.SAXReader;import org.junit.Test;/** * 练习-完整读取xml文档内容 * @author APPle * */public class Demo3 {@Testpublic void test() throws Exception{//读取xml文档SAXReader reader = new SAXReader();Document doc = reader.read(new File("./src/contact.xml"));//读取根标签Element rootELem = doc.getRootElement();StringBuffer sb = new StringBuffer();getChildNodes(rootELem,sb);System.out.println(sb.toString());}/** * 获取当前标签的所有子标签 */private void getChildNodes(Element elem,StringBuffer sb){//System.out.println(elem.getName());//开始标签sb.append("<"+elem.getName());//得到标签的属性列表List<Attribute> attrs = elem.attributes();if(attrs!=null){for (Attribute attr : attrs) {//System.out.println(attr.getName()+"="+attr.getValue());sb.append(" "+attr.getName()+"=\""+attr.getValue()+"\"");}}sb.append(">");//得到文本//String content = elem.getText();//System.out.println(content);Iterator<Node> it = elem.nodeIterator();while(it.hasNext()){Node node = it.next();//标签if(node instanceof Element){Element el = (Element)node;getChildNodes(el,sb);}//文本if(node instanceof Text){Text text = (Text)node;sb.append(text.getText());}}//结束标签sb.append("</"+elem.getName()+">");}}

package gz.itcast.a_dom4j_read;import java.io.File;import java.util.ArrayList;import java.util.Iterator;import java.util.List;import org.dom4j.Document;import org.dom4j.Element;import org.dom4j.io.SAXReader;/** * 把xml文档信息封装到对象中 * @author APPle * */public class Demo4 {public static void main(String[] args) throws Exception{List<Contact> list = new ArrayList<Contact>();//读取xml，封装对象SAXReader reader = new SAXReader();Document doc = reader.read(new File("./src/contact.xml"));//读取contact标签Iterator<Element> it = doc.getRootElement().elementIterator("contact");while(it.hasNext()){Element elem = it.next();//创建ContactContact contact = new Contact();contact.setId(elem.attributeValue("id"));contact.setName(elem.elementText("name"));contact.setAge(elem.elementText("age"));contact.setPhone(elem.elementText("phone"));contact.setEmail(elem.elementText("email"));contact.setQq(elem.elementText("qq"));list.add(contact);}for (Contact contact : list) {System.out.println(contact);}}}