How do thread-safe collections differ in Java?

What are thread-safe collections in Java?

Thread-safe collections are data structures that are designed to be safely accessed by multiple threads simultaneously.

Can you compare some common thread-safe collections?

Sure! Common thread-safe collections include Vector, Hashtable, and ConcurrentHashMap. Each has its own use cases and performance characteristics.

What are the main differences between ConcurrentHashMap and Hashtable?

ConcurrentHashMap allows concurrent read and write operations without locking the entire map, while Hashtable locks the entire map for each operation, making it less efficient.

When should I use CopyOnWriteArrayList?

Use CopyOnWriteArrayList when you have more reads than writes, as it provides a thread-safe way to iterate over the list without locking.