What are Intrinsic Lock, ReentrantLock and ReadWriteLock in Java?

Java provides various locking mechanisms to ensure thread safety and maintain data integrity. Monitor Locks, Reentrant Locks, and Read-Write Locks are fundamental locks in Java.

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But First, we need to understand why we require locks.

Without having proper synchronization, we can have various unexpected cases like:

• Race Conditions: Occurs when an application’s behaviour depends on the relative timing of events between threads.
• Data Inconsistency: This can be due to threads reading partially updated or stale data.
• Deadlocks: This happens when two or more threads are blocked, waiting for others to release a resource
• LiveLocks: This is when threads change their state without making real progress.

Intrinsic Locks

Intrinsic Locks, also called monitor locks, are the most common form of lock-in Java. We achieve this lock using the synchronized keyword.

Synchronized Methods

public class Counter {
    private int count = 0;
    
    public synchronized void increment() {…