code: public static <T> Iterator<T> iterator(T[] a) {
          return DefaultTypeTransformation.asCollection(a).iterator();
      }
docs: Attempts to create an Iterator for the given object by first
  converting it to a Collection.
  
  @param a an array
  @return an Iterator for the given Array.
  @see org.codehaus.groovy.runtime.typehandling.DefaultTypeTransformation#asCollection(java.lang.Object[])
  @since 1.6.4