What is the Optional class in Java?

Question

Accepted Answer

**Optional** — a container that may or may not hold a non-null value, preventing NullPointerException. ```java // Creation Optional user = Optional.ofNullable(findUser(id)); // Safe access String name = user .map(User::getName) .orElse("Unknown"); // With exception String email = user .map(User::getEmail) .orElseThrow(() -> new UserNotFoundException(id)); // Filter Optional admin = user.filter(u -> u.isAdmin()); // FlatMap Optional

address = user .flatMap(User::getAddress); ``` **Best practices:** - Never create with `new Optional()`. - Don't call get() without isPresent(). - Use orElse/orElseThrow instead of get(). - Don't use in collections (use Optional for return values).

Java: What is the Optional class in Java?