Object Serialization

• The idea is to take an object and place it on the stream. It forms the basis of RMI.
• Remember that we are talking about an instance of an object. That is, only the data members and the type of object.
• An class that implements the Serializable marker interface can be serialized. The class has to have a zero-parameter constructor. Also, any static and transient data members will not be serialized.

//To write
FileOutputSream fos = new FileOutputStream("object.dat");
ObjectOutputStream oos = new ObjectOutputStream(fos);

//YourClass is serializable
YourClass yc = new YourClass();
oos.writeObject(yc);

//To read.
FileInputStream fis = new FileInputStream ("object.dat");
ObjectInputStream ois = new ObjectInputStream (fis);
YourClass yc;
yc = (YourClass) ois.readObject();


//You can also check the type of the object before casting it.
FileInputStream fis = FileinputStream("object.dat");
ObjectInputStream ois = new ObjectInputStream(fis);
Object object;
object = ois.readObject();
if (object instanceof YourClass)
{
  YourClass yc = object;
  // Perform operations with yc;
}
else if (object instance of AnotherClass)
{
  AnotherClass ac = object;
  // Perform operations with ac
}