Request-Reply Messaging App

A distributed messaging system implementing a simple request-reply protocol. This project enables users to create accounts, send and receive messages, and manage their inboxes using a client-server architecture.

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Features

• Account Management: Create and view user accounts.
• Messaging: Send and receive messages between users.
• Inbox Management: View, read, and delete messages.
• Authentication: Secure user requests with unique tokens.

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Technologies Used

• Language: Java
• Communication: Socket-based protocol or Remote Method Invocation (RMI)
• Concurrency: Multithreading for handling multiple clients simultaneously

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System Architecture

Server

• Listens for incoming client requests.
• Manages user accounts and their associated messages.
• Spawns threads to handle concurrent client requests.

client

• Acts as the user interface for interacting with the server.
• Supports commands for creating accounts, sending messages, and managing the inbox.

Core Components

• Message: Represents individual messages with attributes like sender, receiver, body, and read status.
• Account: Represents user accounts with details such as username, authentication token, and inbox.

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Installation

1. Clone the repository:

   git clone https://github.com/mpamposd/Server-Client.git
   cd Server-Client

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Usage

Start the Server

Run the server with the following command:

java -jar jars/Server.jar <port_number>

Example:

java -jar jars/Server.jar 5000

Run the Client

Use the client to interact with the server:

java -jar jars/client.jar <server_ip> <port> <function_id> <arguments>

Example for creating a new account:

java -jar jars/client.jar localhost 5000 1 new_user

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Commands

Function ID	Command Example	Description
1	java -jarclient.jar localhost 5000 1 username	Creates a new user account.
2	java -jar client.jar localhost 5000 2 authToken	Lists all existing user accounts.
3	java -jar client.jar localhost 5000 3 authToken recipient body	Sends a message to another user.
4	java -jar client.jar localhost 5000 4 authToken	Displays the user's inbox.
5	java -jar client.jar localhost 5000 5 authToken message_id	Reads a specific message.
6	java -jar client.jar localhost 5000 6 authToken message_id	Deletes a specific message.

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Directory Structure

messaging-app/
│
├── src/                # Source code
│   ├── Server.java
│   ├── client.java
│
├── jars/               # Compiled JAR files
│   ├── Server.jar
│   └── client.jar
│
└── README.md           # Project documentation

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Contributing

Contributions are welcome! To contribute:

1. Fork the repository.
2. Create a feature branch.
3. Commit your changes.
4. Open a pull request.

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License

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Contact

For questions or support, please contact:

• Name: Dimitrios Bampos
• Email: [email protected]