? Java Concurrency Utilities

? Quick Overview

Java Concurrency Utilities are part of the java.util.concurrent package. They provide high-level APIs to manage threads, synchronization, thread pools, and concurrent tasks efficiently and safely.

? Key Concepts

• Thread Pools
• Executor Framework
• Callable and Future
• Synchronization Utilities
• Locks and Atomic Variables

? Syntax / Theory

The concurrency utilities abstract low-level thread handling and help developers write scalable and maintainable multithreaded applications.

• ExecutorService manages a pool of threads
• Callable returns a result from a thread
• Future represents the result of async computation
• Locks provide advanced synchronization

? Code Example

// Example demonstrating ExecutorService with Runnable
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class ExecutorDemo {
public static void main(String[] args) {
ExecutorService executor = Executors.newFixedThreadPool(2);

executor.execute(() -> {
// Task executed by thread pool
System.out.println("Task 1 running");
});

executor.execute(() -> {
// Another concurrent task
System.out.println("Task 2 running");
});

executor.shutdown();
}
}

? Fixed Thread Pool Simulator

Visualizing Executors.newFixedThreadPool(3). Add tasks to see how 3 threads handle the queue.

? Live Output / Explanation