UNIVERSITY OF WEST ATTICA
SCHOOL OF ENGINEERING
DEPARTMENT OF COMPUTER ENGINEERING AND INFORMATICS

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Distributed Systems

Theater Reservation System with Java RMI

Vasileios Evangelos Athanasiou
Student ID: 19390005

GitHub · LinkedIn

Supervisor: Doka Katerina, Senior Researcher

UNIWA Profile · LinkedIn

Athens, June 2023

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Project Overview

This project implements a Java RMI (Remote Method Invocation) application that allows multiple clients to reserve seats for a theater performance at Theater X. The application consists of a server (THServer), a client (THClient), a remote interface (THInterface), and the implementation of this interface (THImpl). The server manages seat reservations and notifies clients of availability.

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Table of Contents

Section	Folder / File	Description
1	assign/	Assignment material
1.1	assign/DS-LAB-ASK-2-2022-23.pdf	Laboratory assignment description (English)
1.2	assign/ΚΣ-ΕΡΓΑΣΤΗΡΙΟ-ΑΣΚ-2-2022-23.pdf	Περιγραφή εργαστηριακής άσκησης (Greek)
2	docs/	Theoretical documentation
2.1	docs/Java-Remote-Method-Invocation.pdf	Java RMI theory (English)
2.2	docs/Απομακρυσμένη-Κλήση-Μεθόδου-Java.pdf	Απομακρυσμένη Κλήση Μεθόδου – Java (Greek)
3	src/	Source code implementation
3.1	src/THServer.java	Remote server main program
3.2	src/THImpl.java	Remote object implementation
3.3	src/THInterface.java	Remote interface definition
3.4	src/THClient.java	Client main program
3.5	src/THClientImpl.java	Client-side object implementation
3.6	src/THClientInterface.java	Client-side interface
3.7	src/AvailableSeats.java	Supporting class: seat management
3.8	src/Reservations.java	Supporting class: reservation management
4	README.md	Repository overview and usage instructions

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Key Features

• Concurrent Server: The server can handle multiple client requests simultaneously.
• Available Seats: The theater offers:
  • 100 PA type seats (Square - Zone A) at 45 Euros each
  • 200 PB type seats (Square - Zone B) at 35 Euros each
  • 400 PC type seats (Square - Zone C) at 25 Euros each
  • 225 KE type seats (Central Exit) at 30 Euros each
  • 75 PTH type seats (Side Theories) at 20 Euros each
• Client Commands:
  • List Available Seats: Clients can list all available seats and their prices.
  • Reserve Seats: Clients can reserve a specified number of seats.
  • List Reservations: Clients can view all reservations made.
  • Cancel Reservations: Clients can cancel their reservations.
• Subscription for Notifications: Clients can subscribe for immediate notifications when seats become available again after a cancellation.

Program Workflow

1. Client Initialization: Clients run the TheaterClient application, specifying commands and parameters.
2. Seat Management:
   • Clients can list available seats.
   • Clients can reserve seats by providing the type, number, and their name.
   • Clients can view their reservations.
   • Clients can cancel their reservations, with the option to subscribe for notifications if they receive a failure message during booking.
3. Server Processing: The TheaterServer manages the reservation process, updates available seats, and communicates with the RMI registry.
4. Notifications: When a seat is canceled, all subscribed clients receive immediate notifications.

Requirements

• Java Development Kit (JDK): Ensure you have JDK 8 or higher installed.
• RMI Registry: The RMI registry must be running on the specified host.
• Java Libraries: Ensure that your Java environment supports RMI.

Installation & Usage

1. Clone the Repository

Download the repository to your local machine:

git clone https://github.com/Distributed-Systems-aka-Uniwa/RMI.git

2. Compile the Classes

Compile the Java classes using the following command:

javac *.java

3. Start the RMI Registry

Start the RMI registry in a terminal:

rmiregistry

4. Run the Theater Server

In a new terminal, start the Theater Server:

java THServer

5. Run the Theater Client

Open multiple terminals to run the client for testing multiple users:

java THClient

6. Usage Instructions

To list available seats:

java THClient list <hostname>

To book seats:

java THClient book <hostname> <type> <number> <name>

To view all reservations:

java THClient guests <hostname>

To cancel reservations:

java THClient cancel <hostname> <type> <number> <name>

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Open the Documentation

1. Navigate to the docs/ directory
2. Open the report corresponding to your preferred language:
   • English: Java-Remote-Method-Invocation.pdf
   • Greek: Απομακρυσμένη-Κλήση-Μεθόδου-Java.pdf