OOP Lab Task 1

Required Tutorials

• The Object Oriented Paradigm; Classes and Objects
• Notions About the Java Language
• Writing and Executing a Java Program
• Java Syntax; A Program's Lexical Structure
• Java Coding Conventions

Requirements

• Create a Java application project whose name contains your name and group using the format group_surname_name (use a single name and a single surname). Student John Codebreaker from 421G will create a project named 421G_Codebreaker_John .
• Add to your project a class Message (that may be used some time in the future as a data carrier between a chat client and all the other clients connected to a server). This class needs to:
  • Store the name of the sender and a message content.
  • Be immutable (once an object of this type is created, its contents can't be changed).
  • Allow reading of the sender and content information from Message objects in a way specific to chat programs: "sender: contents". This must be done using only one method call that returns the formatted string, ready to be displayed by any print method. Try first with a method of your own. Then, add another method, that does exactly the same thing but whose declaration is public String toString().

• Write another class called Main (the default class created if you created a project within NetBeans), which should contain only the main method, that instantiates at least three objects of type Message and then displays their formatted string on the screen.

Notes:

• Each class and class member must have one of the two access modifiers public or private.
• The names of the classes must be identical to the ones specified above.
• Follow the coding rules stated in Java Coding Conventions.

Submitting:

• The assignment will be evaluated automatically by the WebCAT platform.
• You could access the Web-CAT platform using the username and the password with which you acces the studenti.pub.ro intranet.
• If your username and password are valid you should be able to enter your Web-CAT student page (but there is still no course attached to you). If you are unable to acces studenti.pub.ro, contact the UPB net administrator.
• To be enrolled in the OOP lab on the Web-CAT platform you should first add your identification info (intranet username, name, surname, group, e-mail address) into the user registration document. Your registration is checked by the administrator, therefore it may finish after a couple of days.
• Once you are enrolled in the Web-CAT OOP lab, you may submit your work to the active task assignemnts.
• To submit your work you upload a single .zip archive containing only the Java source code files.
• If your work contains a single Java file you may directly upload that single file, unarchived.
• Attention Any deviation from these instructions may lead to the loss of the entire amount of points.