Implementing Public Chat Rooms

Welcome! In this lesson, we'll build public chat rooms. These are common spaces where many users can send and receive messages, visible to everyone in that room.

Think of a general discussion channel in a messaging app. The key characteristic here is broadcast communication: one message sent by any user is instantly relayed to all other users currently in the room.

In Spring with STOMP, we use topics to represent chat rooms. A topic is like a channel clients can subscribe to. Messages sent to a topic are broadcast to all its subscribers.

• For public rooms, we often use a common topic path like /topic/public-chat.
• Clients subscribe to this topic to receive messages.
• Clients send messages to a specific application destination, which the server then forwards to the topic.