If a single implementation, as in @zsmb13’s answer, is not enough for you and you need separate implementations for the two methods in Kotlin, then you can add an intermediate interface overriding the method accepting Integer with a nullable parameter: private interface IntermediateA : A { override fun get(i: Int?): Any } Implementing this interface … Read more
The value parameter is automatically converted to a vararg parameter in Kotlin, as described in http://kotlinlang.org/docs/reference/annotations.html#java-annotations. The correct syntax for this particular case is @OneOf(“m”, “f”)
You can also use the @Value annotation within the constructor: class Test( @Value(“\${my.value}”) private val myValue: Long ) { //… } This has the benefit that your variable is final and none-nullable. I also prefer constructor injection. It can make testing easier.
First, you need to obtain a Field and enable it can be accessible in Kotlin, for example: val field = ABC::class.java.getDeclaredField(“mPrivateField”) field.isAccessible = true Then, you can read the field value as Int by Field#getInt from the instance of the declaring class, for example: val it: ABC = TODO() val value = field.getInt(it) Last, your … Read more
Just fyi you can call list1 == list2 without any extra work, if your custom object is based off of a data class (which automatically overrides equals for you).
Unit in Kotlin is mostly equivalent to void in Java, however only when the rules of the JVM allow it. Functional types in Kotlin are represented by interfaces like: public interface Function1<in P1, out R> : Function<R> { /** Invokes the function with the specified argument. */ public operator fun invoke(p1: P1): R } When … Read more
It’s impossible at the moment in Kotlin to have a property with a setter that is more visible than the property. There’s a language design issue in the issue tracker on this, feel free to watch/vote for it or share your use cases: https://youtrack.jetbrains.com/issue/KT-3110
There’s the spread operator which is denoted by *. The spread operator is placed in front of the array argument: antMatchers(*angularRoutings) For further information, see the documentation: When we call a vararg-function, we can pass arguments one-by-one, e.g. asList(1, 2, 3), or, if we already have an array and want to pass its contents to … Read more