undertow-io/undertow
Undertow
Undertow is a Java HTTP web server and non-blocking I/O server implementation. It functions as a Jakarta Servlet container and a WebSocket server, providing the infrastructure to execute standardized servlet components and maintain persistent full-duplex communication channels for real-time data exchange.
The project is characterized by an asynchronous architecture that utilizes a non-blocking I/O model to handle large numbers of concurrent connections. It incorporates buffer-pooling mechanisms and zero-copy data transfers to reduce memory allocation and garbage collection pressure.
The system manages network traffic through an event-driven handler chain and leverages the XNIO network framework to abstract low-level socket operations. This allows for the integration of a servlet-compatible pipeline within a high-throughput networking environment.
Features
- HTTP Servers - Provides a high-performance core server engine designed to handle, route, and serve web traffic using the HTTP protocol.
- Jakarta Servlet Containers - Implements a full Jakarta Servlet container to execute standardized server-side components and manage Java web applications.
- Servlet Container Implementations - Implements the Jakarta Servlet specification using a modular pipeline architecture for request processing.
- Non-Blocking TCP Servers - Implements a server-side non-blocking model to handle thousands of concurrent connections without tying up system threads.
- WebSocket Clients and Servers - Provides both server-side and client-side toolkits for implementing the bidirectional WebSocket protocol.
- WebSocket Servers - Provides a communication engine that implements persistent bidirectional channels for real-time data exchange.
- Non-blocking I/O - Utilizes a non-blocking I/O model to handle large numbers of concurrent connections with a small number of threads.
- High-Performance HTTP Servers - Optimized for low-latency, high-throughput web service delivery using non-blocking input and output.
- Java Web Hosting Platforms - Functions as a web application server optimized for hosting and executing Java-based servlet applications.
- Real-Time Communication - Establishes persistent, bidirectional data streaming channels for real-time communication between clients and servers.
- Request Handler Chains - Routes incoming byte streams through an event-driven handler chain to parse protocols and execute business logic.
- Asynchronous Network Frameworks - Leverages XNIO as a foundational asynchronous network framework for low-level socket operations and buffer management.
- Byte Buffer Pooling - Uses a shared pool of byte arrays to reduce garbage collection overhead during high-volume I/O operations.
- Zero-Copy Network Transfers - Moves data from network buffers directly to the output stream to minimize memory copying and CPU overhead.
