ReentrantLock is an implementation of the Lock interface that provides more flexible and advanced locking mechanisms compared to the synchronized keyword.

  • Reentrant: If a thread already holds the lock, it can re-enter and acquire the lock again without causing a deadlock. The lock is released only when the thread calls unlock() the same number of times it called lock().
  • Advanced features:
    • tryLock(): Attempts to acquire the lock without blocking.
    • lockInterruptibly(): Acquires the lock but can be interrupted if the thread is waiting.
    • newCondition(): Creates a new Condition object, allowing for more complex inter-thread communication than wait() and notify().

In summary, ReentrantLock allows more control over synchronization and thread interaction, offering reentrant behavior and additional features like lock interruption and non-blocking attempts.