When should thread-safe collections be used in multithreaded applications?

Thread-safe collections in Java should be used when multiple threads read and modify the same collection simultaneously. This is necessary to prevent:

• Race conditions, where data can be corrupted.
• ConcurrentModificationException during iteration.

Examples of such collections include: ConcurrentHashMap, CopyOnWriteArrayList.

Using thread-safe collections simplifies synchronization and increases the reliability of multi-threaded applications.