serodriguez68 / java-rmi-chat-example

This is a simple java rmi app that illustrates how to use java rmi to push messages from a server it's clients.

Intro

This is a very simple java RMI client and server applications for a command line chat.

The purpose of this project is to illustrate how Java RMI can be used for both sending data to a server and pushing data for the server to the clients without the need of handling raw TCP or UDP socket communication.

Overview

Remote

• Contains all remote interfaces that will be shared by both the server and the clients.
• This interfaces represent "the communication contract" between the server and the client.

Server

This package contains all the server related logic

• ChatServerDriver: Entry point to the server program. Creates a server instance and binds it to the RMI registry.
• ChatServer: This class contains all the functionality that our chat service provides. It provides it's services to remote clients by implementing the remote ChatServerInterface.

Client

This package contains all the client related logic

• ChatServerDriver: Entry point to the client program. Locates the remote server using the RMI registry, creates a a chatClient instance and registers the instance with the remote server.
• chatClient: This class contains all the behaviour of our chatting client. It allows the server to push new messages by implementing the ChatClientInterface.

Configuration

RMI is a bit tricky to setup, so grab a hot drink and follow these steps.

1. Open a terminal and make sure that you can use rmiregistry anywhere. This implies adding rmiregistry to your PATH.
2. On a terminal, go to the root of this project and then cd into cd ./out/production/rmi-chat.
3. Start the rmiregistry FROM THAT LOCATION. This is done by typing rmiregistry.
4. You need to modify your IDE's run configuration for both the ChatServerDriver and the ClientServerDriver as follows: In VM Options write: -Djava.rmi.server.codebase=file:/path/to/project/rmi-chat/out/production/rmi-chat
5. Additionally ChatServerDriver needs a command line argument to start (e.g. Alice).

You are all set! You should be able to try this on your localhost with multiple clients on different terminal sessions.