To Be Creative: Using java.beans.XMLEncoder and XMLDecoder

05 March 2010

Using java.beans.XMLEncoder and XMLDecoder

java.beans.XMLEncoder and java.beans.XMLDecoder provides functionality similar to one of java.io.ObjectInputStream and java.io.ObjectOutputStream in which it can serialize an Object ( or graph of Objects) to some streams to be used later.

I've created a simple example here on how to use it :

Here's the Person Class that to be serialized:


package org.daz.xml;

public class Person implements java.io.Serializable{
    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    private String firstName;
    private String lastName;
    private int age;
    
    // Don't forget the Default Constructor
    public Person() {
    }
    
    public Person(String fName, String lName, int age) {
        this.firstName = fName;
        this.lastName = lName;
        this.age = age;
    }
    
    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 getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
}

And Here's The Encoder :


package org.daz.xml;

import java.beans.XMLDecoder;
import java.beans.XMLEncoder;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URISyntaxException;

public class XMLEncoderTest<T> {
    
    private static final String FILE_PATH = "org/daz/xml/persons.xml";
    
    public static void main(String[] args) throws Exception{
        XMLEncoderTest<Person> personEncoder = new XMLEncoderTest<Person>();
        Person person = new Person("Ahmed", "Talat", 23);
        personEncoder.encode(person);
        Person p = personEncoder.decode(true);
        System.out.println("Result : ");
        System.out.println(p.getFirstName() + " \t" + p.getLastName() + "\t" + p.getAge());
    }
    
    public void encode(T object) throws Exception{
        OutputStream stream = new FileOutputStream(new File(XMLEncoderTest.class.getClassLoader().getResource(FILE_PATH).toURI()));
        XMLEncoder encoder = new XMLEncoder(stream);
        encoder.writeObject(object);
        encoder.close();
    }
    
    public T decode(boolean showXml) throws IOException{
        InputStream inStream = XMLEncoderTest.class.getClassLoader().getResourceAsStream(FILE_PATH);
        XMLDecoder decoder = new XMLDecoder(inStream);
        T t = (T) decoder.readObject();
        decoder.close();
        
        if (showXml) {
            printXML();
        }
        return t;
    }
    
    private void printXML()throws IOException{
        InputStream inStream = XMLEncoderTest.class.getClassLoader().getResourceAsStream(FILE_PATH);
        ByteArrayOutputStream byteStream = new ByteArrayOutputStream();
        byte[] buf = new byte[inStream.available()];
        inStream.read(buf);
        byteStream.write(buf);
        System.out.println("Raw XML : \n" + byteStream.toString());
    }
}