Network-Based Chat Application

This is a network-based chat application built using the Java Socket API. It supports real-time communication between clients and provides essential chat room functionalities. The application is implemented with four key classes: Server, ClientThread, Client, and Addressing.

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Features

1. Client-Side Functionalities

• Reconnection Handling:

  • The client attempts to reconnect to the server at set intervals if a connection is lost.
  • If reconnection fails, the client prompts the user to either close the application or enter another port number.

• Chat Commands:

  1. \q - Exits the chat room and closes the client.
  2. #userlist - Displays a list of all active users in the chat room.
  3. #* - Sends a private message to a specified user (e.g., #ann sends a direct message to the user "ann").

• Username Handling:

  • If a username is already taken, a numerical suffix is automatically appended to the username.

• Message Prefixing:

  • Messages in the chat room are prefixed with the sender's username.

• User Join/Leave Notifications:

  • Users are notified when someone enters or leaves the chat room.

2. Chat Room Functionalities

• Multi-User Chat:

  • The server supports multiple clients simultaneously through multithreading.

• Private Messaging:

  • Users can send direct messages to specific individuals in the chat room.

3. Server-Side Functionalities

• Port Logging:

  • The server logs the port numbers of connected clients.

• Resource Management:

  • When a client disconnects, the server confirms the closure of the client's I/O resources in the console log.

4. Networking Functionalities

• Utilizes Java's Socket and ServerSocket APIs to establish TCP connections between the client and server.
• Threads handle client connections, ensuring efficient communication for multiple users.

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Implementation Overview

Key Classes

1. Server

   • Creates a ServerSocket to listen for incoming connections.
   • Uses the accept() method to establish a Socket connection with clients.
   • Handles multiple client connections via the ClientThread class.

2. ClientThread

   • Implements Runnable to handle communication with individual clients on separate threads.
   • Enables simultaneous message exchanges with multiple clients.

3. Client

   • Creates a Socket to connect to the server.
   • Implements sendMessage() to send messages and listen() to receive incoming messages.
   • Runs the listen() method in a separate thread to allow real-time message handling while awaiting user input.

4. Addressing

   • Contains shared methods for assigning IP addresses and port numbers for both client and server applications.

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Prerequisites

• Java Development Kit (JDK): Version 8 or above.
• Integrated Development Environment (IDE): Eclipse, IntelliJ IDEA, or any text editor with Java support.

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Installation

1. Clone the repository or download the source code.

   git clone https://github.com/your-username/java-socket-chat-app.git

2. Open the project in your IDE.
3. Compile the Java files:

   javac *.java

4. Run the server application first, then start one or more client applications.

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Usage

Server Application

1. Run the server application.
2. Enter a valid port number when prompted.
3. The server will start listening for connections and log activity in the console.

Client Application

1. Run the client application.
2. Follow the prompts:
   • Enter an IP address (default: localhost).
   • Enter a valid port number.
   • Input a username.
3. The client will attempt to connect to the server and display a message indicating whether the connection was successful.

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License

This project is licensed under the GNU General Public License v3.0. See the LICENSE file for details.

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Contact

For further information, contact:

• Name: pj-oboyle
• GitHub: pj-oboyle

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Thank you for exploring this project! If you found it useful, please give it a star on GitHub.