CopyOnWriteArrayList was introduced in Java 1.5. It implements

List interface.

It provides better concurrent access methods than a Synchronized

List.

In CopyOnWriteList, concurrency is achieved by copying ArrayList

over each write and replace with original instead of locking.

CopyOnWriteArrayList also does not throw any

ConcurrentModification Exception during Iteration.

It is a thread-safe list.

It is different from a Vector in terms of Concurrency.

CopyOnWriteArrayList provides better Concurrency by reducing

contention among readers and writers.

https://www.tutorialspoint.com/Difference-between-ArrayList-and-CopyOnWriteArrayList-in-Java#:~:text=CopyOnWriteArrayList%20is%20thread%20safe.&text=ArrayList%20iterator%20is%20fail%2Dfast,never%20throw%20ConcurrentModificationException%20during%20iteration.