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I have an array that I want to permutate randomly. In Java, there is a method Collections.shuffle() that can shuffle the elements of a List randomly. It can be used on an array too: String[] array = new String[]{"a", "b", "c"}; // Shuffle the array; works because the list returned by Arrays.asList() is backed by the array Collections.shuffle(Arrays.asList(array)); I tried using this on a Scala array, but the Scala interpreter responds with a lengthy answer: scala> val a = Array("a", "b", "c") a: Array[java.lang.String] = Array(a, b, c) scala> java.util.Collections.shuffle(java.util.Arrays.asList(a)) <console>:6: warning: I'm seeing an array passed into a Java vararg. I assume that the elements of this array should be passed as individual arguments to the vararg. Therefore I follow the array with a `: _*', to mark it as a vararg argument. If that's not what you want, compile this file with option -Xno-varargs-conversion. java.util.Collections.shuffle(java.util.Arrays.asList(a)) ^ <console>:6: error: type mismatch; found : Array[java.lang.String] required: Seq[Array[java.lang.String]] java.util.Collections.shuffle(java.util.Arrays.asList(a)) ^ What exactly is happening here? I don't want to compile my code with a special flag (-Xno-varargs-conversion), if that is the solution at all, just because of this. So, how do I use Java's Collections.shuffle() on a Scala array? I wrote my own shuffle method in Scala in the meantime: // Fisher-Yates shuffle, see: http://en.wikipedia.org/wiki/Fisher–Yates_shuffle def shuffle[T](array: Array[T]): Array[T] = { val rnd = new java.util.Random for (n <- Iterator.range(array.length - 1, 0, -1)) { val k = rnd.nextInt(n + 1) val t = array(k); array(k) =

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