The Java CopyOnWriteArrayList is a thread-safe variant of Java ArrayList in which all mutative operations (like Java add() and Java remove()) are implemented by making a copy of the underlying array. This approach ensures that reading operations can be performed without locking and without interference from writing threads. Introduced in Java 2004 with Java 5, CopyOnWriteArrayList is useful for scenarios where read operations are more frequent than write operations.

https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/CopyOnWriteArrayList.html