1、xml解析有三个方式：
DOM（document object Model）：整个类型装入
SAX（Simple API for XML）：这个是边解析边装入，很好的解决了性能问题，典型的推模式，这个是服务器端为主导
STAX（Streaming API for XML）：这个也是边解析边装入的，不过这个是拉模式，就是说客户端为主导，（安卓 个人理解，减轻了客户端的性能消耗）。
用到的开发包：
JAXP(Java API for XML Processing )：是 Sun 提供的一套XML解析API，包含在javase中。
DOM解析思想：
1、 获取文档建立的总工厂
2、 得到工厂后，获取文档建立者
3、 用文档建立者加载文档到内存，获取到文档对象
4、 用API中的方法进行操作xml
5、 public class DomParse {
6、 @Test
7、 public void test() throws ParserConfigurationException, SAXException,
8、 IOException {
9、 DocumentBuilderFactory builderFactory = DocumentBuilderFactory
10、 .newInstance();// 拿到工厂
11、 DocumentBuilder builder = builderFactory.newDocumentBuilder();// 获取解析器
12、 Document document = builder.parse("books.xml");// 装载文档到内存
13、 NodeList nodeList = document.getElementsByTagName("name");// 通过元素名称来获取元素
14、 String s = null;
15、 for (int i = 0; i < nodeList.getLength(); i++) {// 遍历得到的节点
16、 Element e = (Element) nodeList.item(i);
17、 System.out.println("------------这里没有强制转换类型---------------");
18、 System.out.println(nodeList.item(i).getNodeName());// 获取元素的名称
19、 System.out.println(nodeList.item(i).getNodeValue());// 获取value的值
20、 System.out.println(nodeList.item(i).getTextContent());// 这个是用来获取文本内容
21、 System.out.println("--------------这里进行了强制类型转换-----------");
22、 System.out.println(e.getNodeName());
23、 System.out.println(e.getNodeValue());
24、 System.out.println(e.getTextContent());
25、 if (e.getTextContent().equals("深入理解java")) {
26、 System.out.println("==========================");
27、 System.out.println(e.getNextSibling().getNextSibling()
28、 .getTextContent());// 空格也是一个节点+++这个地方是个易错点，空格也是一个节点
29、 System.out.println("=========================");
30、 }
31、 }
32、
33、 }
34、 }
CURD：creat 、updata、read、delete
用推模式进行SAX解析
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
public class SAXTest {
public static void main(String[] args) throws Exception, Exception {
SAXParserFactory saxParserFactory = SAXParserFactory.newInstance();// 这个是获得工厂
SAXParser saxParser = saxParserFactory.newSAXParser();// 这个是得到解析器
saxParser.parse("server.xml", new MyHandler());// 对文档进行解析
}
}
class MyHandler extends DefaultHandler {
@Override
public void characters(char[] ch, int start, int length)
throws SAXException {
String string = new String(ch, start, length);
System.out.println("字符开始：" + string);
}
@Override
public void endDocument() throws SAXException {
System.out.println("文档结束");
}
@Override
public void startDocument() throws SAXException {
System.out.println("文档开始：");
}
@Override
public void startElement(String uri, String localName, String qName,
Attributes attributes) throws SAXException {
System.out.println("元素开始：" + qName);
}
}
DOM解析之CURD（creat、updata、read、delete）实例
package cn.binbin.xmlParse;
import java.io.File;
import java.io.IOException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.junit.Test;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
public class CURDbook {
@Test
public void delet() throws Exception {
DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory
.newInstance();
DocumentBuilder documentBuilder = documentBuilderFactory
.newDocumentBuilder();
Document document = documentBuilder.parse("books.xml");
// 这个地方时删除节点，方法是先获取父节点，然后在用父节点来删除子节点，不允许自杀
NodeList nodeList = document.getElementsByTagName("name");
for (int i = 0; i < nodeList.getLength(); i++) {
// System.out.println(nodeList.item(i).getTextContent());
if (nodeList.item(i).getTextContent().contains("java")) {
Element book = (Element) nodeList.item(i).getParentNode();
System.out.println(book.getNodeName());
System.out.println(book.getParentNode().getNodeName());
book.getParentNode().removeChild(book);
i--;
}
}
// 开始回写
TransformerFactory transformerFactory = TransformerFactory
.newInstance();
Transformer transformer = transformerFactory.newTransformer();
DOMSource domSource = new DOMSource(document);
StreamResult result = new StreamResult("books_bak.xml");
transformer.transform(domSource, result);
}
@Test
public void updata() throws ParserConfigurationException, SAXException,
IOException, TransformerException {
DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory
.newInstance();
DocumentBuilder documentBuilder = documentBuilderFactory
.newDocumentBuilder();
Document document = documentBuilder.parse("books.xml");
// 先获取节点，然后在修改节点，在回执节点
NodeList nodeList = document.getElementsByTagName("name");
for (int i = 0; i < nodeList.getLength(); i++) {
if (nodeList.item(i).getTextContent().equals("深入理解java")) {
nodeList.item(i).getNextSibling().getNextSibling()
.setTextContent(
Double.parseDouble(nodeList.item(i)
.getNextSibling().getNextSibling()
.getTextContent())
* 1.2 + "");
}
}
// 开始回写
TransformerFactory transformerFactory = TransformerFactory
.newInstance();
Transformer transformer = transformerFactory.newTransformer();
DOMSource domSource = new DOMSource(document);
StreamResult result = new StreamResult("books_bak.xml");
transformer.transform(domSource, result);
}
@Test
public void creat() throws ParserConfigurationException, SAXException,
IOException, TransformerException {
DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory
.newInstance();
DocumentBuilder documentBuilder = documentBuilderFactory
.newDocumentBuilder();
Document document = documentBuilder.parse("books.xml");
// 2、创建name节点
// 1、（创建book节点）创建节点元素，将元素加入到指定位置
Element newbook = document.createElement("book");
Element name = document.createElement("name");
name.setTextContent("编程高手");
newbook.appendChild(name);
// 找到位置
Element root = document.getDocumentElement();
root.appendChild(newbook);
// 开始回写
TransformerFactory transformerFactory = TransformerFactory
.newInstance();
Transformer transformer = transformerFactory.newTransformer();
DOMSource domSource = new DOMSource(document);
StreamResult result = new StreamResult("books_bak.xml");
transformer.transform(domSource, result);
}
@Test
// 修改就应该回写，这里是回写
public void transform() throws ParserConfigurationException, SAXException,
IOException, TransformerException {
DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory
.newInstance();
DocumentBuilder documentBuilder = documentBuilderFactory
.newDocumentBuilder();
Document document = documentBuilder.parse("books.xml");
// 回写,有来有回
TransformerFactory transformerFactory = TransformerFactory
.newInstance();
Transformer transformer = transformerFactory.newTransformer();
DOMSource domSource = new DOMSource(document);// 这个地方是用的DOMSource源
StreamResult streamResult = new StreamResult(new File("book_bak.xml"));// 这个是用流式输出结果集
transformer.transform(domSource, streamResult);// 这个地方用到了回写器
}
}