import java.io.*;
import java.awt.Rectangle;

public class Transient extends Rectangle {

// a field marked transient because it does not need serializing
// this can be calculate from width, height

protected transient int surfaceArea;

//-------------------------------------------------------------------
// main() entry point
//-------------------------------------------------------------------
public static void main (String[] args) {
Object anObject;

	anObject = new Transient(10,33);
	System.out.println("Original object : " + anObject);

	saveObject(anObject, "trans.ser");
	anObject = null;		// loose original object
	anObject = (Transient) loadObject("trans.ser");
	System.out.println("Restored object : " + anObject);
}
//-------------------------------------------------------------------
// Transient constructor
//-------------------------------------------------------------------
public Transient(int width, int height) {
	super(width, height);
	this.surfaceArea = width*height;
}
//-------------------------------------------------------------------
// utility function to save an object to a file
//-------------------------------------------------------------------
public static void saveObject(Object x, String filename) {
FileOutputStream file;
ObjectOutputStream freezer;

	// freeze x into an external file
	try {
		file	= new FileOutputStream(filename);
		freezer = new ObjectOutputStream(file);

		freezer.writeObject( x );
		freezer.close();
	} catch (IOException noIO) {
		System.out.println("IO error occurred: " + noIO);
	}
}
//-------------------------------------------------------------------
// utility function to load an object from a file
//-------------------------------------------------------------------
public static Object loadObject(String filename) {
Object x = null;
FileInputStream file;
ObjectInputStream defreezer;

	// load first object contained in external file
	try {
		file	 = new FileInputStream(filename);
		defreezer= new ObjectInputStream(file);

		x = defreezer.readObject();
		defreezer.close();
	} catch (IOException noIO) {
		System.out.println("IO error occurred: " + noIO);
	} catch ( ClassNotFoundException unknownClass ) {
		System.out.println("Serialized object is of unknown type: " +
			unknownClass);
	}
	return x;
}
//-------------------------------------------------------------------
// custom toString() for our Transient class
//-------------------------------------------------------------------
public String toString() {
	return super.toString()+" area="+ surfaceArea;
}
} // End of Class Transient