⚙️ Executor Framework

? Quick Overview

The Executor Framework in Java provides a high-level API for managing and executing threads. Instead of manually creating and controlling threads, developers submit tasks to an executor service which handles thread creation, scheduling, and lifecycle management.

? Key Concepts

• Executor – Simple interface for executing tasks
• ExecutorService – Manages task lifecycle and thread pool
• Thread Pool – Reusable group of worker threads
• Callable – Task that returns a result
• Future – Represents the result of an async computation

? Syntax / Theory

The framework is available in the java.util.concurrent package and supports different types of thread pools such as fixed, cached, and single-thread executors.

? Code Example(s)

// Creating a fixed thread pool with 2 threads
ExecutorService executor = Executors.newFixedThreadPool(2);

// Submitting a simple Runnable task
executor.submit(() -> {
System.out.println("Task executed by: " + Thread.currentThread().getName());
});

// Shutting down the executor service
executor.shutdown();

// Callable task that returns a value
Callable task = () -> {
return 10 + 20;
};

// Single thread executor
ExecutorService service = Executors.newSingleThreadExecutor();

// Submitting Callable and getting Future
Future result = service.submit(task);

// Fetching result from Future
System.out.println(result.get());

service.shutdown();

? Live Output / Explanation