[java] Difference between `Optional.orElse()` and `Optional.orElseGet()`

Take these two scenarios:

Optional<Foo> opt = ...
Foo x = opt.orElse( new Foo() );
Foo y = opt.orElseGet( Foo::new );

If opt doesn't contain a value, the two are indeed equivalent. But if opt does contain a value, how many Foo objects will be created?

P.s.: of course in this example the difference probably wouldn't be measurable, but if you have to obtain your default value from a remote web service for example, or from a database, it suddenly becomes very important.

Examples related to java

Under what circumstances can I call findViewById with an Options Menu / Action Bar item? How much should a function trust another function How to implement a simple scenario the OO way Two constructors How do I get some variable from another class in Java? this in equals method How to split a string in two and store it in a field How to do perspective fixing? String index out of range: 4 My eclipse won't open, i download the bundle pack it keeps saying error log

Examples related to java-8

Default interface methods are only supported starting with Android N Class has been compiled by a more recent version of the Java Environment Why is ZoneOffset.UTC != ZoneId.of("UTC")? Modify property value of the objects in list using Java 8 streams How to use if-else logic in Java 8 stream forEach Android Studio Error: Error:CreateProcess error=216, This version of %1 is not compatible with the version of Windows you're running Error:could not create the Java Virtual Machine Error:A fatal exception has occured.Program will exit What are functional interfaces used for in Java 8? java.time.format.DateTimeParseException: Text could not be parsed at index 21 Java 8 lambda get and remove element from list

Examples related to optional

Java 8 optional: ifPresent return object orElseThrow exception Default optional parameter in Swift function Difference between `Optional.orElse()` and `Optional.orElseGet()` Why should Java 8's Optional not be used in arguments Why use Optional.of over Optional.ofNullable? Java 8 - Difference between Optional.flatMap and Optional.map Check string for nil & empty How to execute logic on Optional if not present? Swift: Testing optionals for nil Proper usage of Optional.ifPresent()