### Question:
IntSinglyLinkedList implements Serializable, Iterable<Integer> { public boolean isEmpty() { return size == 0; } IntSinglyLinkedList(); int size(); boolean contains(int item); void addLast(int item); void addFirst(int item); boolean isEmpty(); void clear(); int pop(); int peek(); void push(int item); int dequeue(); int getFirst(); void enqueue(int item); int[] toArray(); Integer[] toObjArray(); @Override String toString(); @Override boolean equals(Object other); @Override int hashCode(); @Override IntListIterator iterator();  }### Answer:
@Test public void testIsEmpty() { IntSinglyLinkedList list = new IntSinglyLinkedList(); list.enqueue(0); list.enqueue(1); list.pop(); assertFalse(list.isEmpty()); }