### Question:
InPlaceLeftRotator implements Rotator<E, MutableBinaryTreeNode<E>> { @Override public Class<?> forClass() { return MutableBinaryTreeNodeImpl.class; }  @Override void rotate(ParentReference<MutableBinaryTreeNode<E>> reference, MutableBinaryTreeNode<E> currentRoot); @Override RotationDirection forDirection(); @Override Class<?> forClass();  }### Answer:
@Test public void forClass() { final InPlaceLeftRotator<String> rotator = new InPlaceLeftRotator<>(); assertEquals(MutableBinaryTreeNodeImpl.class, rotator.forClass()); }