W3Schools Tryit Editor

import java.io.*;

public class Main {
  public static void main(String[] args) {
  	Person person = new Person();
    person.fname = "John";
    person.lname = "Doe";
    person.age = 24;
    person.accessCode = 5044;
  
    // Serialize the object
  	ByteArrayOutputStream output = new ByteArrayOutputStream();
  	try {
      ObjectOutputStream objOut = new ObjectOutputStream(output);
      objOut.writeObject(person);
    } catch (IOException e) {}
    
    // Deserialize the object
    Person person2 = new Person();
    try {
    ObjectInputStream objIn = new ObjectInputStream(new ByteArrayInputStream(output.toByteArray()));  
    person2 = (Person)objIn.readObject();  
  	} catch(Exception e) {}
    
    // Print the deseralized object
    System.out.println("First name: " + person2.fname);
    System.out.println("Last name: " + person2.lname);
    System.out.println("Age: " + person2.age);
    System.out.println("Access code: " + person2.accessCode);
  }
}

class Person implements Serializable {
  String fname = "John";
  String lname = "Doe";
  int age = 24;
  transient int accessCode = 0;
}