At first glance it is needed just convert collection to array and pass it to method but this does not work:
val toTypedArray = Arrays.asList("a", "b").toTypedArray()
Paths.get("", toTypedArray) // <- compilation error here
No workarounds???
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Jonah Starling
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Cherry
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What do you want to achieve in that? – Abdul Waheed Sep 26 '17 at 05:43
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2Also you should probably use Kotlin's `arrayOf ` instead of `Arrays.asList` – Seaskyways Sep 26 '17 at 05:50
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Is is just example to show the problem. There is no any goals about passing `"a","b"` to `Paths.get` method – Cherry Sep 26 '17 at 06:05
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Note that when the function requires non-null primitive type, e.g. `vararg numbers: Int`, you have to use `toIntArray()` instead of `toTypedArray()`. – BakaWaii Sep 26 '17 at 06:24
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@Seaskyways `Arrays.asList(...)` returns a list, so the replacement would be `listOf(...)` – Ruckus T-Boom Sep 26 '17 at 15:58
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@RuckusT-Boom that is true, however lists are not usable with the spread operator, only arrays are :) – Seaskyways Sep 26 '17 at 19:40
1 Answers
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An Array can be passed as anvararg argument by prepending * to it:
Paths.get("", *toTypedArray)
It’s called spread operator, as I already described in another answer here.
An instance of List can be converted to vararg as follows:
val listAsArr =
listOf("a", "b").toTypedArray()
Paths.get("", *listAsArr)
s1m0nw1
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