1，Student类
package com.yangw.xml;
import javax.xml.bind.annotation.XmlRootElement;
@XmlRootElement //作为根节点的元素需要设置这个注解
public class Student {
private int id;
private String name;
private int age;
private Classroom classroom;
public Student(int id, String name, int age, Classroom classroom) {
super();
this.id = id;
this.name = name;
this.age = age;
this.classroom = classroom;
}
.... get set ...
}
2， Classroom对象
package com.yangw.xml;
public class Classroom {
private int id;
private String name; //班级名称
private int grade; //年级
public Classroom(int id, String name, int grade) {
super();
this.id = id;
this.name = name;
this.grade = grade;
}
public Classroom() {
super();
}
... get set ...
}
3， 测试类，对象与xml互转
package com.yangw.xml;
import java.io.StringReader;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;
import org.junit.Test;
public class TestJaxb {
/**
* 编排：对象转成xml
*/
@Test
public void test01() {
try {
JAXBContext ctx=JAXBContext.newInstance(Student.class);
Marshaller marshaller=ctx.createMarshaller();
Student stu=new Student(1,"张",20,new Classroom(1,"软件工程01",2008));
//参数： 对象，输出流
marshaller.marshal(stu, System.out);
} catch (JAXBException e) {
e.printStackTrace();
}
}
/**
* 反编排：xml转成对象
*/
@Test
public void test02() {
try {
JAXBContext ctx=JAXBContext.newInstance(Student.class);
Unmarshaller um=ctx.createUnmarshaller();
String xml="<?xml version='1.0' encoding='UTF-8' standalone='yes'?><student><age>20</age><classroom><grade>2008</grade><id>1</id><name>软件工程01</name></classroom><id>1</id><name>张</name></student>";
//参数： 对象，输出流
Student stu=(Student)um.unmarshal(new StringReader(xml));
System.out.println(stu.getName()+"-->"+stu.getClassroom().getName());
} catch (JAXBException e) {
e.printStackTrace();
}
}
}
4, Stax解析xml
<?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>
package com.yangw.stax;
import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
import javax.xml.namespace.QName;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.stream.EventFilter;
import javax.xml.stream.XMLEventReader;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamConstants;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.events.Attribute;
import javax.xml.stream.events.XMLEvent;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
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 TestStax {
/**
* Stax，基于光标的解析xml
*/
@Test
public void test() {
//1,创建工厂
XMLInputFactory factory=XMLInputFactory.newInstance();
//2，创建XMLStreamReader
InputStream is=null;
is=TestStax.class.getClassLoader().getResourceAsStream("books.xml");
try {
XMLStreamReader reader=factory.createXMLStreamReader(is);
while(reader.hasNext()){
switch(reader.next()){
case XMLStreamConstants.START_ELEMENT:
//获取开始标签名
String name=reader.getName().toString();
if("book".equals(name)){
//获取属性名属性值
System.out.println(reader.getAttributeName(0)+":"+reader.getAttributeValue(0));
}else if("price".equals(name)){
//获取节点的文本
System.out.println(reader.getElementText());
}
break;
case XMLStreamConstants.END_ELEMENT:
break;
case XMLStreamConstants.ATTRIBUTE:
break;
case XMLStreamConstants.CHARACTERS:
break;
}//switch
}//while
} catch (XMLStreamException e) {
e.printStackTrace();
}finally{
try {
if(is!=null){
is.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* Stax，基于迭代模型的解析xml
*/
@SuppressWarnings("unchecked")
@Test
public void test02() {
//1,创建工厂
XMLInputFactory factory=XMLInputFactory.newInstance();
//2，创建XMLStreamReader
InputStream is=null;
is=TestStax.class.getClassLoader().getResourceAsStream("books.xml");
try {
XMLEventReader reader=factory.createXMLEventReader(is);
while(reader.hasNext()){
//通过XMLEvent来判断是否是某种节点
XMLEvent event=reader.nextEvent();
if(event.isStartElement()){
//先转换为开始节点，再获取值
QName qName=event.asStartElement().getName();
if("book".equals(qName.toString())){
//获取属性
//一个值的方式
Attribute attr1= event.asStartElement().getAttributeByName(new QName("category"));
System.out.println(attr1.getValue());
//多个值进行迭代
Iterator<Attribute> it=event.asStartElement().getAttributes();
while(it.hasNext()){
Attribute attr=it.next();
System.out.println(attr.getName()+":"+attr.getValue());
}
}else if("price".equals(qName.toString())){
//获取节点的文本
System.out.println(reader.getElementText());
}
}
}//while
} catch (XMLStreamException e) {
e.printStackTrace();
}finally{
try {
if(is!=null){
is.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* Stax，基于迭代模型的解析xml，增加了Filter
*/
@SuppressWarnings("unchecked")
@Test
public void test03() {
//1,创建工厂
XMLInputFactory factory=XMLInputFactory.newInstance();
//2，创建XMLStreamReader
InputStream is=null;
is=TestStax.class.getClassLoader().getResourceAsStream("books.xml");
try {
//基于Filter的过滤方式，可以有效的过滤掉不用进行操作的节点，效率会高一点
XMLEventReader reader=factory.createFilteredReader(factory.createXMLEventReader(is),
new EventFilter(){
@Override
public boolean accept(XMLEvent event) {
//能够接受的条件就返回true
if(event.isStartElement()){
//假如只过滤book节点
String name=event.asStartElement().getName().toString();
if("book".equals(name)){
return true;
}
}
return false;
}});
while(reader.hasNext()){
//通过XMLEvent来判断是否是某种节点
XMLEvent event=reader.nextEvent();
if(event.isStartElement()){
//先转换为开始节点，再获取值
String name=event.asStartElement().getName().toString();
if("book".equals(name)){
//获取属性
//一个值的方式
Attribute attr1= event.asStartElement().getAttributeByName(new QName("category"));
System.out.println(attr1.getValue());
//多个值进行迭代
Iterator<Attribute> it=event.asStartElement().getAttributes();
while(it.hasNext()){
Attribute attr=it.next();
System.out.println(attr.getName()+":"+attr.getValue());
}
}else if("price".equals(name)){
//获取节点的文本
System.out.println(reader.getElementText());
}
}
}//while
} catch (XMLStreamException e) {
e.printStackTrace();
}finally{
try {
if(is!=null){
is.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* Stax，基于xPath的解析xml,它需要将这个文档加到内存中
*/
@SuppressWarnings("unchecked")
@Test
public void test04() {
InputStream is=null;
is=TestStax.class.getClassLoader().getResourceAsStream("books.xml");
try {
//DocumentBuilder
DocumentBuilder builder=DocumentBuilderFactory.newInstance().newDocumentBuilder();
//文档处理对象
Document doc=builder.parse(is);
XPath xPath=XPathFactory.newInstance().newXPath();
//使用xPath查找
// (表达式，源，返回类型急查找出来的类型)
NodeList list=(NodeList) xPath.evaluate("//book[@category='WEB']", doc, XPathConstants.NODESET);
for(int i=0;i<list.getLength();i++){
//Node有很多的子类 ，这个返回的是Element
Element ele=(Element) list.item(i); //book节点
//获取该节点的title信息
System.out.println(ele.getElementsByTagName("title").item(0).getTextContent());
}
} catch (ParserConfigurationException e) {
e.printStackTrace();
} catch (SAXException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (XPathExpressionException e) {
e.printStackTrace();
}
}
}
5， 写xml。使用Stax
/**
* Stax，新建xml
*/
@SuppressWarnings("unchecked")
@Test
public void test05() {
OutputStream ops=null;
try {
ops=System.out;
XMLOutputFactory factory=XMLOutputFactory.newInstance();
XMLStreamWriter writer=factory.createXMLStreamWriter(ops);
writer.writeStartDocument("utf-8", "1.0");
writer.writeEndDocument();
String ns="http://yangw.com";
writer.writeStartElement("yang", "person", ns);
writer.writeNamespace("yang", ns);
writer.writeNamespace("xsi","http://www.w3.org/2001/XMLSchema-instance");
writer.writeAttribute("id","1");
writer.writeCharacters("yigeren");
writer.writeEndElement();
writer.flush();
writer.close();
} catch (FactoryConfigurationError e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (XMLStreamException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
6， 修改xml内容
/**
* Stax，修改xml节点值，通过 Transformer * 先通过Xpath查找，再通过 Transformer修改
*/
@SuppressWarnings("unchecked")
@Test
public void test06() {
InputStream is=null;
is=TestStax.class.getClassLoader().getResourceAsStream("books.xml");
try {
//DocumentBuilder
DocumentBuilder builder=DocumentBuilderFactory.newInstance().newDocumentBuilder();
//文档处理对象
Document doc=builder.parse(is);
XPath xPath=XPathFactory.newInstance().newXPath();
Transformer tran=TransformerFactory.newInstance().newTransformer();
tran.setOutputProperty(OutputKeys.ENCODING, "utf-8");
tran.setOutputProperty(OutputKeys.INDENT, "yes");
//使用xPath查找
// (表达式，源，返回类型急查找出来的类型)
NodeList list=(NodeList) xPath.evaluate("//book[title='Learning XML']", doc, XPathConstants.NODESET);
//获取price节点
Element be =(Element) list.item(0);
Element e = (Element) be.getElementsByTagName("price").item(0);
e.setTextContent("100.00");
Result result=new StreamResult(System.out);
//通过transformer修改节点
tran.transform(new DOMSource(doc), result);
} catch (ParserConfigurationException e) {
e.printStackTrace();
} catch (SAXException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (XPathExpressionException e) {
e.printStackTrace();
} catch (TransformerConfigurationException e) {
e.printStackTrace();
} catch (TransformerFactoryConfigurationError e) {
e.printStackTrace();
} catch (TransformerException e) {
e.printStackTrace();
}
}