What are Java Reentrant Locks?

Can you explain what Java Reentrant Locks are?

Sure! Java Reentrant Locks are a part of the java.util.concurrent package and provide a way to control access to a shared resource by multiple threads.

How do they differ from synchronized methods?

Reentrant Locks offer more flexibility than synchronized methods. They allow for features like try-lock, timed lock, and the ability to interrupt a thread waiting for a lock.

Can you give me an example of how to use a Reentrant Lock?

Certainly! Here's a simple example:

import java.util.concurrent.locks.ReentrantLock;

public class Example {
    private final ReentrantLock lock = new ReentrantLock();

    public void safeMethod() {
        lock.lock();
        try {
            // critical section code
        } finally {
            lock.unlock();
        }
    }
}

Are there any downsides to using Reentrant Locks?

Yes, one downside is that they can lead to deadlocks if not used carefully. It's important to always ensure that locks are released.