What are the various mechanisms, apart from synchronized locks, to restrict multiple threads from making modifications in Java?

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Accepted Answer

Java provides several mechanisms beyond synchronized locks to manage thread safety and restrict concurrent modifications.

1. ReentrantLock: A more flexible locking mechanism that allows for timed and interruptible locks. Example: ReentrantLock lock = new ReentrantLock();
2. ReadWriteLock: Allows multiple threads to read but only one to write, improving performance for read-heavy scenarios. Example: ReadWriteLock rwLock = new ReentrantReadWriteLock();
3. Atomic Variables: Classes like AtomicInteger and AtomicReference provide lock-free thread-safe operations. Example: AtomicInteger atomicInt = new AtomicInteger(0);
4. Concurrent Collections: Java provides thread-safe collections like ConcurrentHashMap and CopyOnWriteArrayList. Example: ConcurrentHashMap map = new ConcurrentHashMap<>();
5. ThreadLocal: Provides thread-local variables, ensuring that each thread has its own instance. Example: ThreadLocal threadLocalValue = new ThreadLocal<>();

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