10.CopyOnWriteArrayList

1. What it is. This list adopts the idea of separating reads and writes (weak consistency): reads can proceed concurrently without locking; writes require locking, copying the original data, modifying the copy, and then writing it back to the list. 2. How to use it. 3. Principles. 3.1. Constructor. The underlying implementation uses an Object array and accesses it through getArray/setArray.