### Question:
Constructor implements TreeConstructor<E, MutableSettableStructuredNode<E>, LinkedTree<E>> { @Override @SafeVarargs public final LinkedTree<E> build(E e, LinkedTree<E>... subtrees) { return new LinkedTree<>(e, subtrees); }  @Override @SafeVarargs final LinkedTree<E> build(E e, LinkedTree<E>... subtrees); @Override Class<? extends Tree> forClass();  }### Answer:
@Test public void build() { final Constructor<String> constructor = new Constructor<>(); final LinkedTree<String> tree = constructor.build("a"); assertEquals("a", tree.getElement()); assertEquals(0, tree.getNumberOfChildren()); assertFalse(tree.isEmpty()); }