Serialization java example

To implement a very basic example of Serialization in java, lets create Person.java that implements Serializable interface.
Person.java

 package com.serialization;  
 import java.io.Serializable;
 public class Person implements Serializable {  
   private String firstName;  
   private String lastName;  
   public Person(String firstName, String lastName) {  
     super();  
     this.firstName = firstName;  
     this.lastName = lastName;  
   }  
   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;  
   }  
 }  

SerializationMain.java

 package com.serialization;  
 import java.io.FileOutputStream;  
 import java.io.IOException;  
 import java.io.ObjectOutputStream;  
 public class SerializationMain {  
   public static void main(String[] args) throws IOException {  
     Person person = new Person("Kumar", "Bhatia");  
     System.out.println("person " + person);  
     FileOutputStream fos = new FileOutputStream("serial.txt");  
     ObjectOutputStream oos = new ObjectOutputStream(fos);  
     oos.writeObject(person);  
     oos.flush();  
     oos.close();  
   }  
 }  

If "implements Serializable" is removed from Person.java, following exception occurs:

Exception in thread "main" java.io.NotSerializableException: com.serialization.Person
 at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1164)
 at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:330)
 at com.serialization.SerializationMain.main(SerializationMain.java:15)

DeSerializationMain.java

 package com.serialization;  
 import java.io.FileInputStream;  
 import java.io.IOException;  
 import java.io.ObjectInputStream;  
 public class DeSerializationMain {  
   public static void main(String[] args) throws IOException, ClassNotFoundException {  
     FileInputStream fis = new FileInputStream("serial.txt");  
     ObjectInputStream ois = new ObjectInputStream(fis);  
     Person person = (Person) ois.readObject();  
     ois.close();  
     System.out.println("person " + person.getFirstName());  
   }  
 }  

Run DeSerializationMain.java and the output would be same person object that gets serialized.