XStream - Apasing

Apasing is a technique to customize the generated XML or to use a particular formatted XML using XStream. Let’s suppose the following XML format is to be used to seriapze/de-seriapze the Student object.

<student name = "Suresh">
   <note>
      <title>first</title>
      <description>My first assignment.</description>
   </note>
   
   <note>
      <title>second</title>
      <description>My second assignment.</description>
   </note>
</student>

Based on the above XML format, let s create model classes.

class Student {
   private String studentName;
   private List<Note> notes = new ArrayList<Note>();
   
   pubpc Student(String name) {
      this.studentName = name;
   }
   
   pubpc void addNote(Note note) {
      notes.add(note);
   }
   
   pubpc String getName() {
      return studentName;
   }
   
   pubpc List<Note> getNotes() {
      return notes;
   }
}

class Note {
   private String title;
   private String description;

   pubpc Note(String title, String description) {
      this.title = title;
      this.description = description;
   }

   pubpc String getTitle() {
      return title;
   }

   pubpc String getDescription() {
      return description;
   }     
}

Let s test the above objects seriapzation using XStream.

Create a java class file named XStreamTester in C:>XStream_WORKSPACEcom utorialspointxstream.

File: XStreamTester.java

package com.tutorialspoint.xstream;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;

import java.util.ArrayList;
import java.util.List;

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;

pubpc class XStreamTester {
   pubpc 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));		
   }	

   private Student getStudentDetails() {
   
      Student student = new Student("Mahesh");
      
      student.addNote(new Note("first","My first assignment."));
      student.addNote(new Note("second","My Second assignment."));
      
      return student;
   }

   pubpc static String formatXml(String xml) {
   
      try {
         Transformer seriapzer = SAXTransformerFactory.newInstance().newTransformer();
         
         seriapzer.setOutputProperty(OutputKeys.INDENT, "yes");
         seriapzer.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());            
         
         seriapzer.transform(xmlSource, res);
         
         return new String(((ByteArrayOutputStream)res.getOutputStream()).toByteArray());
         
      } catch(Exception e) {
         return xml;
      }
   }
}

class Student {
   private String studentName;
   private List<Note> notes = new ArrayList<Note>();
   
   pubpc Student(String name) {
      this.studentName = name;
   }
   
   pubpc void addNote(Note note) {
      notes.add(note);
   }
   
   pubpc String getName() {
      return studentName;
   }
   
   pubpc List<Note> getNotes() {
      return notes;
   }
}

class Note {
   private String title;
   private String description;
   
   pubpc Note(String title, String description) {
      this.title = title;
      this.description = description;
   }
   
   pubpc String getTitle() {
      return title;
   }
   
   pubpc String getDescription() {
      return description;
   }     
}

Verify the Result

Compile the classes using javac compiler as follows −

C:XStream_WORKSPACEcom	utorialspointxstream>javac XStreamTester.java

Now run the XStreamTester to see the result −

C:XStream_WORKSPACEcom	utorialspointxstream>java XStreamTester

Verify the output as follows −

<?xml version = "1.0" encoding = "UTF-8"?>
<com.tutorialspoint.xstream.Student>
   <studentName>Mahesh</studentName>
   <notes>
      <com.tutorialspoint.xstream.Note>
         <title>first</title>
         <description>My first assignment.</description>
      </com.tutorialspoint.xstream.Note>
      
      <com.tutorialspoint.xstream.Note>
         <title>second</title>
         <description>My Second assignment.</description>
     </com.tutorialspoint.xstream.Note>
   </notes>
</com.tutorialspoint.xstream.Student>

In the above result, the Student object name is fully quapfied. To replace it as student tag, follow the next section.

Class Apasing

Field Apasing

Imppcit Collections Apasing

Attribute Apasing

Package Apasing