The of() method creates an Optional if a value is present, or forces an immediate NullPointerException otherwise. The Kotlin equivalent of assigning an empty() is to assign a null.
Static Optional absent = Optional.empty() To explore all of the possibilities, we’ll assume these constants: static Optional present = Optional.of("Hello") Then we’ll wrap up with a few more thoughts about the trade-offs between using Optional and using Kotlin with nullable types. In this guide, we’ll take a look at how Kotlin’s null-safety features can be used to replace Java 8’s Optional class. What should you do? Should you leave them as Optional, or change them to more idiomatic Kotlin? When Java 8 introduced Streams for operating on collections of data, it also introduced a similar concept, Optional, which has many methods that are similar to Stream, but operates on a single value that might or might not be present.Īs you migrate your projects from Java to Kotlin, you might come across some Optional objects.
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