Optional<T> is a container object introduced in Java 8 that may or may not hold a non-null value. It’s a better alternative to using null to represent missing values and helps write cleaner, more expressive code.
Scenarios
- When a method might not return a value but you want to avoid returning
null. - To chain operations safely without explicit null checks.
- To make APIs more readable by expressing “optional” values clearly.
Sample Usage
// Creating Optional instances
Optional<String> name = Optional.of("Java");
Optional<String> empty = Optional.empty();
Optional<String> maybeNull = Optional.ofNullable(getUserInput());
// Safe access
name.ifPresent(System.out::println); // prints "Java"
String result = maybeNull.orElse("Default Value");
System.out.println(result);
// Chaining
Optional<String> upper = maybeNull.map(String::toUpperCase);
System.out.println(upper.orElse("NO VALUE"));
// Throw if missing
String mustHave = maybeNull.orElseThrow(() -> new IllegalArgumentException("Missing value"));