CSE116 A,B   Introduction to Computer Science II         Fall 2000
Lab5

Objective: To learn about Serialization that provides object read and write capability to applications.

Introduction: Capability to store and retrieve objects is essential to adding persistence and streaming into application. Key to storing and retrieving objects is representing the "state" of the objects in a serialized form sufficient to reconstruct the objects.
Objects < == > byte stream, other data to help in reconstruction.

Using Serialization:

1. import java.io.*;
2. Objects to be written/read will have to implement java.io.Serialization interface.
3. Use writeObject and readObject methods whose header are as given below:
void writeObject(Object obj) throws IOException
Object readObject() throws ClassNotFoundException, IOException
 
4. Serialize various objects into a file
Example:
FileOutputStream f = new FileOutputStream("tmp");
ObjectOutputStream s = new ObjectOutputStream(f);
s.writeObject("Today");
s.writeObject(new Date());
Location loc = new Location(3.4,5.6); // Location should implement Serializable interface
s.writeObject();
5. Reading from an Object stream.
Example:
FileInputStream inf = new FileInputStream("tmp");
ObjectInputStream s1 = new ObjectInputStream(inf);
String s = (String) s1.readObject();
Date date = (Date)s1.readObject();

6. See Lab4 and observe how Record object is input and output into a file.

What to do for lab5?

Rewrite Location class to implement java.io.Serializable. Location class is available at /projects/bina/cse116/edu/colorado/geometry directory.

Create a LinkedList of Location objects. Let the Linked List have at least 4 objects.

Write the linked list into a file.

Read from the file and print it out to standard output.