🌐 Java Web Server (Single-Threaded & Multithreaded)

A Java-based HTTP web server showcasing three server models: Single-threaded, multi-threaded, and thread-pool based implementations. This project demonstrates practical understanding of Java concurrency, networking, and performance trade-offs.

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🚀 Features

• Single-threaded server implementation
• Multi-threaded server (thread-per-request model)
• Thread pool–based server using ExecutorService
• Handles multiple client connections
• Basic HTTP request parsing
• Supports GET requests
• Clean separation of server and request-handling logic
• Lightweight and dependency-free

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🛠 Tech Stack

• Java 17 (Java 8+ compatible)
• Java Sockets (ServerSocket, Socket)
• Java Threads
• ExecutorService & Thread Pools
• Java I/O Streams

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⚙️ Server Models Implemented

1️⃣ Single-Threaded Server

• Processes one client request at a time
• Simple and easy to understand
• Blocks all incoming requests while processing

Use case: Learning basics of sockets & request handling

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2️⃣ Multi-Threaded Server (Thread-per-Request)

• Creates a new thread for each client connection
• Supports concurrent request handling
• Can lead to high resource usage under heavy load

Use case: Moderate traffic, learning concurrency

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3️⃣ Thread Pool–Based Server

• Uses a fixed-size thread pool via ExecutorService
• Reuses worker threads efficiently
• Prevents uncontrolled thread creation
• Best balance between performance and resource usage

Use case: Production-like server model

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📂 Project Structure

src/
 ├── main/
 │    ├── java/
 │    │    ├── src/
 │    │    │    ├── SingleThreadedServer
 │    │    │    ├── MultiThreadedServer
 │    │    │    ├── ThreadPoolServer

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🔄 Request Handling Flow

1. Server starts and listens on a port

2. Client sends HTTP request

3. Connection is accepted

4. Request is handled based on server model:

   • Single thread
   • New thread per request
   • Thread pool worker

5. HTTP response is returned

6. Connection is closed

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▶️ Running the Server

Single-Threaded

java SingleThreadedServer

Multi-Threaded

java MultiThreadedServer

Thread Pool

java ThreadPoolServer

Server runs at:

http://localhost:8080

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🧪 Testing & Comparison

• Open multiple browser tabs
• Use curl or Apache Bench
• Observe performance differences between models
• Compare response times and throughput

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📈 Future Enhancements

• Configurable thread pool size
• Request queue monitoring
• Support for POST requests
• Static file serving
• Graceful shutdown
• Performance benchmarking