标签：des style c class blog code
以下是我学习webService视频的学习笔记:
1.Java类和XML之间的转换.
ClassInfo.java代码:
public class ClassInfo { private int id; private String className; public ClassInfo(int id, String className) { super(); this.id = id; this.className = className; } public ClassInfo() { super(); } // ..省略getter/setter方法... }
StudentInfo.java代码:
@XmlRootElement public class StudentInfo { private int id; private String stuName; private ClassInfo classInfo; public StudentInfo() { super(); } public StudentInfo(int id, String stuName) { super(); this.id = id; this.stuName = stuName; } //..省略getter/setter方法 }
编排测试方法如下:
// 编排 @Test public void test01() { try { // 使用JAXB方式编排,获取JaxbContext对象 参数为需要编排的类 JAXBContext ctx = JAXBContext.newInstance(StudentInfo.class); // 通过JaxbContext对象创建编排Marshaller对象 Marshaller marshaller = ctx.createMarshaller(); StudentInfo student = new StudentInfo(); student.setId(1); student.setStuName("张璐"); student.setClassInfo(new ClassInfo(1, "java_1")); // 调用编排 参数1:编排对象, 参数2:输出流 marshaller.marshal(student, System.out); } catch (JAXBException e) { e.printStackTrace(); } }
PS:获取jaxbContext对象被作为参数的类,需要加上@XmlRootElement注解.如上的StudentInfo类
反编排测试代码如下:
// 反编排 @Test public void test02() throws Exception{ // 获取JaxbContext对象 JAXBContext ctx = JAXBContext.newInstance(StudentInfo.class); // 创建反编排对象 Unmarshaller um = ctx.createUnmarshaller(); // 创建File,指定xml文件,System.getProperty("user.dir")获取项目路径 File file = new File(System.getProperty("user.dir")+ "/src/com/zhanglu/xml/studentInfo.xml"); StudentInfo stu = (StudentInfo) um.unmarshal(file);// 进行反编排获取对象 System.out.println(stu.getStuName()); }
2.Java中读取XML
在项目的com.zhanglu.xml包中有如下booksxml文件. (来自W3CSHOOL)
<?xml version="1.0" encoding="utf-8"?> <bookstore> <book category="COOKING"> <title lang="en">Everyday Italian</title> <author>Giada De Laurentiis</author> <year>2005</year> <price>30.00</price> </book> <book category="CHILDREN"> <title lang="en">Harry Potter</title> <author>J K. Rowling</author> <year>2005</year> <price>29.99</price> </book> <book category="WEB"> <title lang="en">XQuery Kick Start</title> <author>James McGovern</author> <author>Per Bothner</author> <author>Kurt Cagle</author> <author>James Linn</author> <author>Vaidyanathan Nagarajan</author> <year>2003</year> <price>49.99</price> </book> <book category="WEB"> <title lang="en">Learning XML</title> <author>Erik T. Ray</author> <year>2003</year> <price>39.95</price> </book> </bookstore>
Stream以光标方式读取:
// 使用Stream 光标方式 @Test public void textReader01() throws Exception { XMLInputFactory factory = XMLInputFactory.newInstance();// 获取工厂 InputStream is = TestStax.class.getClassLoader().getResourceAsStream("com/zhanglu/xml/books.xml");// 获取流 XMLStreamReader reader = factory.createXMLStreamReader(is);// 创建stream读取对象 while (reader.hasNext()) {// 如果有下文 循环读取 int tag = reader.next();// 返回获取的下一个常量值 if (XMLStreamConstants.START_ELEMENT == tag) {// 对常量进行判断,如果是开始节点 if (reader.getAttributeCount() > 0) {// 如果节点的属性数理大于0 System.out.println(reader.getName());// 获取节点名称 System.out.println(reader.getAttributeName(0) + "," + reader.getAttributeValue(0));// 输出节点 } } }
}
Event迭代方式读取(普通迭代):
// 迭代方式 EVENT @Test public void textReader03() throws Exception { XMLInputFactory factory = XMLInputFactory.newInstance();// 获取工厂 InputStream is = TestStax.class.getClassLoader().getResourceAsStream("com/zhanglu/xml/books.xml");// 获取流 // 创建exent读取对象 XMLEventReader reader = factory.createXMLEventReader(is); while (reader.hasNext()) {// 遍历 XMLEvent event = reader.nextEvent();// 获取下一个Event if (event.isStartElement()) {// 如果是开始节点 System.out.println(event.asStartElement().toString());// 输出 // System.out.println(event.asStartElement().getName().toString()); } }
}
Event迭代方式读取(使用过滤器来减少迭代次数):
// 迭代方式 EVENT 使用过滤器 减少迭代次数 @Test public void textReader04() throws Exception { XMLInputFactory factory = XMLInputFactory.newInstance();// 获取工厂 InputStream is = TestStax.class.getClassLoader().getResourceAsStream("com/zhanglu/xml/books.xml");// 获取流 XMLEventReader reader = factory.createFilteredReader( factory.createXMLEventReader(is), new EventFilter() {// 获取读取对象,重写EventFilter类的accept方法 @Override public boolean accept(XMLEvent event) { if (event.isStartElement()) {//如果是开始标签,返回true return true;//这样就只会迭代开始标签 } return false; } }); while (reader.hasNext()) { XMLEvent event = reader.nextEvent(); if (event.isStartElement()) {//判断是否为开始标签 System.out.println(event.asStartElement().toString()); } } }
XPath方式读取XML:
//使用Xpath 操作 @Test public void test01() throws Exception{ //创建输入流 InputStream is=TestXpathReader.class.getClassLoader().getResourceAsStream("com/zhanglu/xml/books.xml"); //创建Xpath对象 通过Xpath工厂 XPath xpath=XPathFactory.newInstance().newXPath(); //创建文档对象 通过文档构造工厂 DocumentBuilder db=DocumentBuilderFactory.newInstance().newDocumentBuilder(); Document doc=db.parse(is); //获取节点集合 第一个参数 表达式 第二个文档 第三个Xpath NodeList nodeList=(NodeList)xpath.evaluate("//book[@category=‘WEB‘]", doc,XPathConstants.NODESET); //遍历 for(int i=0;i<nodeList.getLength();i++){ //将节点对象转换为Element对象 Element element=(Element)nodeList.item(i); System.out.println(element.getElementsByTagName("author").item(0).getTextContent()); } }
3.使用Java中的XMLStreamWriter写入一个XML
//使用 XMLStreamWriter 来写xml文件 @Test public void test01() throws Exception{ FileOutputStream out=new FileOutputStream(new File(System.getProperty("user.dir")+"/src/com/zhanglu/xml/student.xml")); XMLStreamWriter w=XMLOutputFactory.newInstance().createXMLStreamWriter(out); w.writeStartDocument("UTF-8", "1.0"); w.writeEndDocument(); w.writeStartElement("student"); w.writeAttribute("stuId", "1"); w.writeStartElement("stuName"); w.writeCharacters("张三"); w.writeEndElement(); w.writeStartElement("stuSex"); w.writeCharacters("男"); w.writeEndElement(); w.writeStartElement("stuAddress"); w.writeCharacters("湖北襄阳"); w.writeEndElement(); w.writeEndElement(); w.flush(); out.close(); }
4.使用TransFormer来更新XML文件
// 使用TransFormer更新xml文件 @Test public void test() throws Exception { // 创建输入流 InputStream is = TestTransFormerUpdate.class.getClassLoader().getResourceAsStream("com/zhanglu/xml/student.xml"); // 创建DocBuilder对象 DocumentBuilder db = DocumentBuilderFactory.newInstance().newDocumentBuilder(); Document doc = db.parse(is);// 获取document对象 XPath xpath = XPathFactory.newInstance().newXPath();// 创建Xpath对象 // 创建transFormer对象 Transformer tran = TransformerFactory.newInstance().newTransformer(); tran.setOutputProperty(OutputKeys.ENCODING, "utf-8");// 设置编码 tran.setOutputProperty(OutputKeys.INDENT, "yes");// 支付插入 tran.setOutputProperty(OutputKeys.VERSION, "1.0");// 版本 // 获取指定的节点集合 NodeList nodes = (NodeList) xpath.evaluate("//student[@stuId=‘1‘]",doc, XPathConstants.NODESET); Element se = (Element) nodes.item(0);// 获取第一个 Element e = (Element) se.getElementsByTagName("stuAddress").item(0); e.setTextContent("湖北襄阳枣阳"); Result result = new StreamResult(new File(System.getProperty("user.dir")+ "/src/com/zhanglu/xml/student.xml")); tran.transform(new DOMSource(doc), result); }
标签：des style c class blog code
原文地址：http://www.cnblogs.com/zhanglu-cape/p/3754917.html
