Task: Object serialization



C#: using System;
using System.IO;
using System.Collections.Generic;
using System.Runtime.Serialization.Formatters.Binary;

namespace Object_serialization
{
  [Serializable] public class Being
  {
    public bool Alive { get; set; }
  }

  [Serializable] public class Animal: Being
  {
    public Animal() { }

    public Animal(long id, string name, bool alive = true)
    {
      Id = id;
      Name = name;
      Alive = alive;
    }

    public long Id { get; set; }
    public string Name { get; set; }

    public void Print() { Console.WriteLine("{0}, id={1} is {2}",
      Name, Id, Alive ? "alive" : "dead"); }
  }


  internal class Program
  {
    private static void Main()
    {
      string path = 
        Environment.GetFolderPath(Environment.SpecialFolder.Desktop)+"\\objects.dat";

      var n = new List<Animal>
              {
                new Animal(1, "Fido"),
                new Animal(2, "Lupo"),
                new Animal(7, "Wanda"),
                new Animal(3, "Kiki", alive: false)
              };

      foreach(Animal animal in n)
        animal.Print();

      using(var stream = new FileStream(path, FileMode.Create, FileAccess.Write))
        new BinaryFormatter().Serialize(stream, n);

      n.Clear();
      Console.WriteLine("---------------");
      List<Animal> m;

      using(var stream = new FileStream(path, FileMode.Open, FileAccess.Read))
        m = (List<Animal>) new BinaryFormatter().Deserialize(stream);

      foreach(Animal animal in m)
        animal.Print();
    }
  }
}



Java: import java.io.*;


class Entity implements Serializable {
    
    
    static final long serialVersionUID = 3504465751164822571L;
    String name = "Entity";
    public String toString() { return name; }
}

class Person extends Entity implements Serializable {
    static final long serialVersionUID = -9170445713373959735L;
    Person() { name = "Cletus"; }
}

public class SerializationTest {
    public static void main(String[] args) {
        Person instance1 = new Person();
        System.out.println(instance1);

        Entity instance2 = new Entity();
        System.out.println(instance2);

        
        try {
            ObjectOutput out = new ObjectOutputStream(new FileOutputStream("objects.dat")); 

            out.writeObject(instance1); 
            out.writeObject(instance2);
            out.close();
            System.out.println("Serialized...");
        } catch (IOException e) {
            System.err.println("Something screwed up while serializing");
            e.printStackTrace();
            System.exit(1);
        }

        
        try {
            ObjectInput in = new ObjectInputStream(new FileInputStream("objects.dat")); 

            Object readObject1 = in.readObject(); 
            Object readObject2 = in.readObject(); 
            in.close();
            System.out.println("Deserialized...");

            System.out.println(readObject1);
            System.out.println(readObject2);
        } catch (IOException e) {
            System.err.println("Something screwed up while deserializing");
            e.printStackTrace();
            System.exit(1);
        } catch (ClassNotFoundException e) {
            System.err.println("Unknown class for deserialized object");
            e.printStackTrace();
            System.exit(1);
        }
    }
}