Home

Atmosphere Framework 4.0

The Atmosphere Framework makes it easy to build real-time web applications using WebSocket and Server-Sent Events (SSE) with automatic fallback to long-polling. It runs on JDK 21+ and integrates with Spring Boot 4.0, Quarkus 3.21+, and any Servlet 6.0+ container.

Atmosphere 4.0 introduces first-class Rooms with presence tracking, message history, and direct messaging — plus a fully rewritten TypeScript client with React, Vue, and Svelte hooks.

Getting Started

Pick your deployment model:

• Getting Started with Spring Boot 4.0 — auto-configured, production-ready
• Getting Started with Quarkus — build-time optimized, native-image ready
• WAR Deployment (Tomcat, GlassFish, etc.) — deploy to any Servlet 6.0+ container
• Getting Started with atmosphere.js 5.0 — TypeScript client library

Core Concepts

• Understanding @ManagedService — the annotation-driven approach for general-purpose endpoints
• Understanding @RoomService — the room-aware alternative with built-in presence and history
• Understanding Rooms — named groups with presence, history, and direct messaging
• Understanding Broadcaster — the pub/sub message bus (includes cache & filters)
• Clustering with Kafka and Redis — scale out across multiple nodes
• Durable Sessions — survive server restarts with SQLite or Redis
• Observability — Micrometer metrics, OpenTelemetry tracing, backpressure

AI / LLM Streaming

• AI Streaming Guide — SPI, built-in LLM client, Spring AI, LangChain4j, Embabel adapters, client hooks

MCP Server

• MCP Server Guide — expose tools, resources, and prompts to AI agents over WebSocket

Kotlin

• Kotlin DSL — idiomatic handler builder and coroutine extensions

Client Libraries

• Getting Started with atmosphere.js 5.0 — TypeScript client: subscribe, transports, rooms
• Framework Hooks — React, Vue, Svelte — useRoom, usePresence, stores
• atmosphere.js API Reference — full type reference
• Java Client (wAsync) — async Java client: WebSocket, SSE, streaming, long-polling, and gRPC

gRPC Transport

• gRPC Transport — bidirectional streaming over HTTP/2, standalone or Spring Boot integrated

Advanced Topics

• Understanding AtmosphereResource — the server-side connection handle
• Understanding AtmosphereInterceptor — request/response pipeline
• Understanding the Atmosphere Protocol — wire format and handshake

Migration

• Migrating from Atmosphere 2.x to 4.0

Samples

Sample	Framework	Source
Chat	WAR / Embedded Jetty	samples/chat
Chat (WebSocket)	Embedded Jetty	samples/embedded-jetty-websocket-chat
Chat + Rooms	Spring Boot 4.0	samples/spring-boot-chat
Chat	Quarkus 3.21	samples/quarkus-chat
AI Chat (built-in LLM)	Spring Boot 4.0	samples/spring-boot-ai-chat
AI Chat (LangChain4j)	Spring Boot 4.0	samples/spring-boot-langchain4j-chat
AI Chat (Embabel Agent)	Spring Boot 4.0	samples/spring-boot-embabel-chat
MCP Server	Spring Boot 4.0	samples/spring-boot-mcp-server
Durable Sessions	Spring Boot 4.0	samples/spring-boot-durable-sessions
gRPC Chat	Embedded gRPC	samples/grpc-chat

Legacy Documentation

Looking for Atmosphere 2.x documentation? See the Legacy Documentation page.