Gradle/Maven dependency DSL examples Simplest example. AnyĪny in Kotlin is on the top of the hierarchy. Kotlin + Mockito MockK mockk, every, Annotation, verify MockK Relaxed Mocks, Verify, Capture Static Method, Singleton Installation All you need to get started is just to add a dependency to MockK library. Note that Nothing is a subtype of Unit, that's why the first compile but not the last one. Or, if you prefer, is the result value of any statement (for example println()). The Unit type in Kotlin is the equivalent to the void type in Java. We will look in detail at Unit, Nothing, and Any, and compare against their Java corresponding classes.įinally, we also consider null and how types ending with ? fit into these categories. To take full advantage of the Kotlin Type Hierarchy, it is essential to understand how these three special types work. It is also quite close to the Java Type System, so the interoperability is excellent.ĥ Things You Will Like in Kotlin as a Java Developer

One of the reasons is its Type Hierarchy, which is both very easy to work with and extremely powerful. First, note that MutableList<> isn't the same as MutableList (it's important here that MutableList is invariant on T).

It should be apparent, even to the casual reader of this blog, that I really like Kotlin as a language. String of pearls How to Take Advantage of Kotlin Special Types

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