assertEquals(4, list.lastIndexOf("b"));
  }

  public void testCopyOfDefensiveCopy() {
    // Depending on JDK version, either toArray() or toArray(T[]) may be called... use this class
    // rather than mocking to ensure that one of those methods is called.
    class TestArrayList<E> extends ArrayList<E> {
      boolean toArrayCalled = false;

      @Override
      public Object[] toArray() {
        toArrayCalled = true;