What are some examples of using semaphores in Java?

What are some examples of using semaphores in Java?

Semaphores in Java are used to control access to a shared resource. Would you like to see a code example?

Yes, please provide a code example.

Here's a simple example:

import java.util.concurrent.Semaphore;

public class SemaphoreExample {
    private static final Semaphore semaphore = new Semaphore(1);

    public static void main(String[] args) {
        Thread thread1 = new Thread(() -> accessResource("Thread 1"));
        Thread thread2 = new Thread(() -> accessResource("Thread 2"));

        thread1.start();
        thread2.start();
    }

    private static void accessResource(String threadName) {
        try {
            semaphore.acquire();
            System.out.println(threadName + " has acquired the semaphore.");
            // Simulate resource access
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            System.out.println(threadName + " is releasing the semaphore.");
            semaphore.release();
        }
    }
}

This code demonstrates how two threads can access a shared resource using a semaphore.

What does the acquire and release method do?

The acquire method decreases the semaphore count, blocking if the count is zero, while release increases the count, allowing other threads to proceed.