java JAXB + STAX（是一种针对XML的流式拉分析API）读取xml

JDK1.5需要添加jar包，1.6以后就不需要了
<dependency>
<groupId>stax</groupId>
<artifactId>stax-api</artifactId>
<version>1.0.1</version>
</dependency>
<dependency>
<groupId>javax.xml.bind</groupId>
<artifactId>jaxb-api</artifactId>
<version>2.2.12</version>
</dependency>

JAXB：JAXB 的全名是Java ™ Architecture for XML Binding

Classroom.java

public class Classroom {
private int id;
private String name;
private int grade;

public Classroom() {
super();
// TODO Auto-generated constructor stub
}

public Classroom(int id, String name, int grade) {
super();
this.id = id;
this.name = name;
this.grade = grade;
}

public int getId() {
return id;
}

public void setId(int id) {
this.id = id;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public int getGrade() {
return grade;
}

public void setGrade(int grade) {
this.grade = grade;
}

@Override
public String toString() {
// TODO Auto-generated method stub
return String.format("id:%d, name:%s, grade:%d", this.id, this.name, this.grade);
}
}

Student.java

@XmlRootElement
public class Student {
public int getId() {
return id;
}

public void setId(int id) {
this.id = id;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public int getAge() {
return age;
}

public void setAge(int age) {
this.age = age;
}

public Classroom getClassroom() {
return classroom;
}

public void setClassroom(Classroom classroom) {
this.classroom = classroom;
}

private int id;
private String name;
private int age;
private Classroom classroom;

public Student() {
super();
// TODO Auto-generated constructor stub
}

public Student(int id, String name, int age, Classroom classroom) {
super();
this.id = id;
this.name = name;
this.age = age;
this.classroom = classroom;
}

@Override
public String toString() {
// TODO Auto-generated method stub
return String.format("id:%d, name:%s, Classroom=>%s", this.id, this.name, this.classroom.toString());
}
}

main方法：

public static void main(String[] args) throws JAXBException {
Student student = new Student(1, "大帅哥", 34, new Classroom(1, "计算机", 1));
JAXBContext jaxbContext = JAXBContext.newInstance(Student.class);
Marshaller marshaller = jaxbContext.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true); //格式化输出
marshaller.marshal(student, System.out);
StringWriter stringWriter = new StringWriter();
marshaller.marshal(student, stringWriter);
String xml = stringWriter.toString();
Unmarshaller unmarshaller = jaxbContext.createUnmarshaller();
student = (Student) unmarshaller.unmarshal(new StringReader(xml));
System.out.println(student.toString());
}

STAX：StAX是Streaming API for XML的缩写，是一种针对XML的流式拉分析API。

使用XMLStreamReader和XMLEventReader读取XML文件

<?xml version="1.0" encoding="UTF-8"?>
<company>
<depart title="Develop Group">
<user name="Tom" age="28" gender="male" >Manager</user>
<user name="Lily" age="26" gender="female" />
</depart>
<depart title="Test Group">
<user name="Frank" age="32" gender="male" >Team Leader</user>
<user name="Bob" age="45" gender="male" />
<user name="Kate" age="25" gender="female" />
</depart>
</company>

JAVA代码

// 获得Stream解析器(指针读取器对象)
public static XMLStreamReader getStreamReader() {
XMLStreamReader reader = null;
String xmlFile = App.class.getResource("/").getFile() + "users.xml";
XMLInputFactory factory = XMLInputFactory.newInstance();
try {
reader = factory.createXMLStreamReader(new FileReader(xmlFile));
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (XMLStreamException e) {
e.printStackTrace();
}
return reader;
}

// 获得Stream解析器(指针读取器对象),过滤器
public static XMLStreamReader getStreamReader(StreamFilter streamFilter) {
// 创建基于迭代器的指针读取器对象
XMLStreamReader filterReader = null;
String xmlFile = App.class.getResource("/").getFile() + "users.xml";
XMLInputFactory factory = XMLInputFactory.newInstance();
try {
XMLStreamReader reader = factory.createXMLStreamReader(new FileReader(xmlFile));
filterReader = factory.createFilteredReader(reader, streamFilter);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (XMLStreamException e) {
e.printStackTrace();
}
return filterReader;
}

// 列出所有用户名称
public static void listNames() {
// 创建基于迭代器的指针读取器对象
XMLStreamReader reader = App.getStreamReader();
// 遍历XML文档
try {
while (reader.hasNext()) {
int event = reader.next();
// 如果是元素的开始
if (event == XMLStreamConstants.START_ELEMENT) {
// 列出所有用户名称
if ("user".equalsIgnoreCase(reader.getLocalName())) {
System.out.println("Name:" + reader.getAttributeValue(null, "name"));
}
}
}
reader.close();
} catch (XMLStreamException e) {
e.printStackTrace();
}
}

public static void listNamesAndAges() {
XMLStreamReader reader = App.getStreamReader();
try {
while (reader.hasNext()) {
// 跳过所有空白、注释或处理指令，到下一个START_ELEMENT
int event = reader.nextTag();
if (event == XMLStreamConstants.START_ELEMENT) {
if ("user".equalsIgnoreCase(reader.getLocalName())) {
System.out.println("Name:" + reader.getAttributeValue(null, "name") + ";Age:" + reader.getAttributeValue(null, "age"));
}
}
}
reader.close();
} catch (XMLStreamException e) {
e.printStackTrace();
}
}

// 获得Event解析器(事件读取器对象)
public static XMLEventReader getEventReader() {
XMLEventReader reader = null;
String xmlFile = App.class.getResource("/").getFile() + "users.xml";
XMLInputFactory factory = XMLInputFactory.newInstance();
try {
reader = factory.createXMLEventReader(new FileReader(xmlFile));
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (XMLStreamException e) {
e.printStackTrace();
}
return reader;
}

// 获得Event解析器(指针读取器对象),过滤器
public static XMLEventReader getEventReader(EventFilter eventFilter) {
// 创建基于迭代器的指针读取器对象
XMLEventReader filterReader = null;
String xmlFile = App.class.getResource("/").getFile() + "users.xml";
XMLInputFactory factory = XMLInputFactory.newInstance();
try {
XMLEventReader reader = factory.createXMLEventReader(new FileReader(xmlFile));
filterReader = factory.createFilteredReader(reader, eventFilter);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (XMLStreamException e) {
e.printStackTrace();
}
return filterReader;
}

@SuppressWarnings("rawtypes")
public static void listAllByXMLEventReader() {
// 创建基于迭代器的事件读取器对象
XMLEventReader reader = App.getEventReader();
try {
// 遍历XML文档
while (reader.hasNext()) {
XMLEvent event = reader.nextEvent();
// 如果事件对象是元素的开始
if (event.isStartElement()) {
// 转换成开始元素事件对象
StartElement start = event.asStartElement();
// 打印元素标签的本地名称
System.out.print(start.getName().getLocalPart());
// 取得所有属性
Iterator attrs = start.getAttributes();
while (attrs.hasNext()) {
// 打印所有属性信息
Attribute attr = (Attribute) attrs.next();
System.out.print(":" + attr.getName().getLocalPart() + "=" + attr.getValue());
}
System.out.println();
}
}
reader.close();
} catch (XMLStreamException e) {
e.printStackTrace();
}
}

public static void listUsersByStreamFilter() {
XMLStreamReader streamFilterReader = App.getStreamReader(new StreamFilter() {
public boolean accept(XMLStreamReader reader) {
try {
while (reader.hasNext()) {
int event = reader.next();
// 只接受元素的开始
if (event == XMLStreamConstants.START_ELEMENT) {
// 只保留user元素
if ("user".equalsIgnoreCase(reader.getLocalName())) {
return true;
}
}
if (event == XMLStreamConstants.END_DOCUMENT) {
return true;
}
}
} catch (XMLStreamException e) {
e.printStackTrace();
}
return false;
}
});
try {
// 列出所有用户的名称
System.out.println(streamFilterReader.getLocalName());
while (streamFilterReader.hasNext()) {
// 过滤工作已交由过滤器完成，这里不需要再做user的判断了
System.out.println("Name=" + streamFilterReader.getAttributeValue(null, "name"));
if (streamFilterReader.getEventType() != XMLStreamConstants.END_DOCUMENT) {
streamFilterReader.next();
}
}
streamFilterReader.close();
} catch (XMLStreamException e) {
e.printStackTrace();
}
}

public static void listUsersByEventFilter() {
XMLEventReader eventFilterReader = App.getEventReader(new EventFilter() {
public boolean accept(XMLEvent event) {
// 如果事件对象是元素的开始
if (event.isStartElement()) {
// 转换成开始元素事件对象
StartElement start = event.asStartElement();
// 打印元素标签的本地名称
return "user".equals(start.getName().getLocalPart());
}
return false;
}
});
try {
// 列出所有用户的名称
while (eventFilterReader.hasNext()) {
XMLEvent event = eventFilterReader.nextEvent();
StartElement start = event.asStartElement();
System.out.println(start.getName().getLocalPart());
// 过滤工作已交由过滤器完成，这里不需要再做user的判断了
System.out.println("Name=" + start.getAttributeByName(new QName("name")).getValue());
}
eventFilterReader.close();
} catch (XMLStreamException e) {
e.printStackTrace();
}
}

public static void main(String[] args) {
// listNames();
// listNamesAndAges();
// listAllByXMLEventReader();
// listUsersByStreamFilter();
// listUsersByEventFilter();
}

转自：http://blog.chinaunix.net/uid-20749563-id-718396.html

转自：/article/4144451.html