XStream - 第一个应用程序

在进入XStream库的细节之前，让我们看看一个正在运行的应用程序.在这个例子中，我们创建了Student和Address类.我们将创建一个student对象，然后将其序列化为XML String.然后反序列化相同的XML字符串以获取学生对象.

在 C:\> XStream_WORKSPACE 中创建名为XStreamTester的java类文件./p>

文件:XStreamTester.java

import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import javax.xml.transform.OutputKeys;import javax.xml.transform.Source;import javax.xml.transform.Transformer;import javax.xml.transform.sax.SAXSource;import javax.xml.transform.sax.SAXTransformerFactory;import javax.xml.transform.stream.StreamResult;import org.xml.sax.InputSource;import com.thoughtworks.xstream.XStream;import com.thoughtworks.xstream.io.xml.StaxDriver;public class XStreamTester {   public static void main(String args[]) {      XStreamTester tester = new XStreamTester();      XStream xstream = new XStream(new StaxDriver());            Student student = tester.getStudentDetails();            //Object to XML Conversion      String xml = xstream.toXML(student);      System.out.println(formatXml(xml));            //XML to Object Conversion      Student student1 = (Student)xstream.fromXML(xml);      System.out.println(student1);   }      private Student getStudentDetails() {         Student student = new Student();      student.setFirstName("Mahesh");      student.setLastName("Parashar");      student.setRollNo(1);      student.setClassName("1st");      Address address = new Address();      address.setArea("H.No. 16/3, Preet Vihar.");      address.setCity("Delhi");      address.setState("Delhi");      address.setCountry("India");      address.setPincode(110012);      student.setAddress(address);      return student;   }      public static String formatXml(String xml) {         try {         Transformer serializer = SAXTransformerFactory.newInstance().newTransformer();                  serializer.setOutputProperty(OutputKeys.INDENT, "yes");         serializer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "2");                  Source xmlSource = new SAXSource(new InputSource(            new ByteArrayInputStream(xml.getBytes())));         StreamResult res =  new StreamResult(new ByteArrayOutputStream());                              serializer.transform(xmlSource, res);                  return new String(((ByteArrayOutputStream)res.getOutputStream()).toByteArray());               } catch(Exception e) {         return xml;      }   }}class Student {   private int rollNo;   private String firstName;   private String lastName;   private String className;   private Address address;   public String getFirstName() {      return firstName;   }      public void setFirstName(String firstName) {      this.firstName = firstName;   }      public String getLastName() {      return lastName;   }      public void setLastName(String lastName) {      this.lastName = lastName;   }      public int getRollNo() {      return rollNo;   }      public void setRollNo(int rollNo) {      this.rollNo = rollNo;   }      public String getClassName() {      return className;   }      public void setClassName(String className) {      this.className = className;   }      public Address getAddress() {      return address;   }      public void setAddress(Address address) {      this.address = address;   }      public String toString() {      StringBuilder stringBuilder = new StringBuilder();            stringBuilder.append("Student [ ");      stringBuilder.append("\nfirstName: ");      stringBuilder.append(firstName);      stringBuilder.append("\nlastName: ");      stringBuilder.append(lastName);      stringBuilder.append("\nrollNo: ");      stringBuilder.append(rollNo);      stringBuilder.append("\nclassName: ");      stringBuilder.append(className);      stringBuilder.append("\naddress: ");      stringBuilder.append(address);      stringBuilder.append(" ]");            return stringBuilder.toString();   }}class Address {   private String area;   private String city;   private String state;   private String country;   private int pincode;   public String getArea() {      return area;   }   public void setArea(String area) {      this.area = area;   }   public String getCity() {      return city;   }   public void setCity(String city) {      this.city = city;   }   public String getState() {      return state;   }   public void setState(String state) {      this.state = state;   }   public String getCountry() {      return country;   }   public void setCountry(String country) {      this.country = country;   }   public int getPincode() {      return pincode;   }   public void setPincode(int pincode) {      this.pincode = pincode;   }   public String toString() {      StringBuilder stringBuilder = new StringBuilder();      stringBuilder.append("\nAddress [ ");      stringBuilder.append("\narea: ");      stringBuilder.append(area);      stringBuilder.append("\ncity: ");      stringBuilder.append(city);      stringBuilder.append("\nstate: ");      stringBuilder.append(state);      stringBuilder.append("\ncountry: ");      stringBuilder.append(country);      stringBuilder.append("\npincode: ");      stringBuilder.append(pincode);      stringBuilder.append(" ]");      return stringBuilder.toString();   }}

验证结果

编译使用 javac 编译器的类如下 :

C:\XStream_WORKSPACE>javac XStreamTester.java

现在运行XStreamTester查看结果 :

C:\XStream_WORKSPACE>java XStreamTester

验证输出如下

   Mahesh   Parashar   1   1st   
      H.No. 16/3, Preet Vihar.      Delhi      Delhi      India      110012   Student [    firstName: Mahesh   lastName: Parashar   rollNo: 1   className: 1st   address:    Address [       area: H.No. 16/3, Preet Vihar.      city: Delhi      state: Delhi      country: India      pincode: 110012   ] ]

要记住的步骤

以下是需要考虑的重要步骤.

步骤1:创建XStream对象

通过传递StaxDriver创建一个XStream对象. StaxDriver使用Stax pull解析器(可从java 6获得)并且是一个快速的xml解析器.

XStream xstream = new XStream(new StaxDriver());

步骤2:将对象序列化为XML

使用toXML()方法获取XML的字符串表示形式对象.

//Object to XML ConversionString xml = xstream.toXML(student);

步骤3:反序列化XML以获取对象

使用fromXML()方法从中获取对象XML.

//XML to Object ConversionStudent student1 = (Student)xstream.fromXML(xml);