- Serialization is a mechanism of converting a java object into byte stream.
- Deserialization is reverse of serialization in which byte stream is converted back to a java object in memory.
- Byte stream created is platform independent so, the object serialized on one platform can be deserialized on other platform.
- For making java object serializable we must have to implements java.io.Serializable interface.
- We can serialize an object from writeObject() method which is defined in ObjectOutputStream class.
- We can deserialize an object from readObject() method which is defined in ObjectInputStream class.
Serialization and De-Serialization Example :-
import java.io.*;
class Emp implements Serializable {
private static final long serialversionUID =129348938L;
transient int a;
int b;
String name;
int age;
public Emp(String name, int age, int a, int b)
{
this.name = name;
this.age = age;
this.a = a;
this.b = b;
}
}
public class SerialExample {
public static void printdata(Emp object1)
{
System.out.println("name = " + object1.name);
System.out.println("age = " + object1.age);
System.out.println("a = " + object1.a);
System.out.println("b = " + object1.b);
}
public static void main(String[] args)
{
Emp object = new Emp("ab", 20, 2, 1000);
String filename = "shubham.txt";
// Serialization
try {
// Saving of object in a file
FileOutputStream file = new FileOutputStream(filename);
ObjectOutputStream out = new ObjectOutputStream(file);
// Method for serialization of object
out.writeObject(object);
out.close();
file.close();
System.out.println("Object has been serialized\n"
+ "Data before Deserialization.");
printdata(object);
// value of static variable changed
object.b = 2000;
}
catch (IOException ex)
{
System.out.println("IOException is caught");
}
object = null;
// Deserialization
try {
// Reading the object from a file
FileInputStream file = new FileInputStream(filename);
ObjectInputStream in = new ObjectInputStream(file);
// Method for deserialization of object
object = (Emp)in.readObject();
in.close();
file.close();
System.out.println("Object has been deserialized\n"
+ "Data after Deserialization.");
printdata(object);
// System.out.println("z = " + object1.z);
}
catch (IOException ex) {
System.out.println("IOException is caught");
}
catch (ClassNotFoundException ex) {
System.out.println("ClassNotFoundException" +
" is caught");
}
}
}
