* to dump the queue into a newly allocated array of {@code String}:
   *
   * <pre>
   *     String[] y = x.toArray(new String[0]);</pre>
   *
   * <p>Note that {@code toArray(new Object[0])} is identical in function to {@code toArray()}.
   *
   * @param a the array into which the elements of the queue are to be stored, if it is big enough;
   *     otherwise, a new array of the same runtime type is allocated for this purpose

   * to dump the queue into a newly allocated array of {@code String}:
   *
   * <pre>
   *     String[] y = x.toArray(new String[0]);</pre>
   *
   * <p>Note that {@code toArray(new Object[0])} is identical in function to {@code toArray()}.
   *
   * @param a the array into which the elements of the queue are to be stored, if it is big enough;
   *     otherwise, a new array of the same runtime type is allocated for this purpose