You can't cast Object[] to String[] in Java

Consider this snippet:
String[] str = (String[]) new Object[] { "Bla!"};.
That gives a ClassCastException. The short version of an explanation: an array instantiated by new Object[] is of a different class than one by new String[]. For the full glory of that fact, please see the Java Language Specification. As a teaser, I'll quote this snippet and its output from it:

class Test {
 public static void main(String[] args) {
  int[] ia = new int[3];
  System.out.println(ia.getClass());
  System.out.println(ia.getClass().getSuperclass());
 }
}

which prints:
class [I
class java.lang.Object.