scala> def f[A: Manifest](a: A) = java.util.Arrays.asList(Array(a): _*)
f: [A](a: A)(implicit evidence$$1: Manifest[A])java.util.List[A]

scala> f("")
res0: java.util.List[java.lang.String] = []

scala> f(0)
java.lang.ClassCastException: [I cannot be cast to [Ljava.lang.Object;

scala> java.util.Arrays.asList(Array(0): _*)
res17: java.util.List[Int] = r0

scala> res17.asInstanceOf[java.util.List[_ <: AnyRef]].get(0).getClass
res18: java.lang.Class[_] = class java.lang.Integer

scala> def g[A](a: A*) = ()
g: [A](a: A*)Unit

scala> def h[A: Manifest](a: A) = g(Array(a): _*)
h: [A](a: A)(implicit evidence$$1: Manifest[A])Unit

scala> h("")

scala> h(0)