MyStack implements SimpleStack<T> { public boolean hasNext() { return depth > 0; } MyStack();  MyStack(int howBig); @Override boolean empty(); @Override void push(T obj); @Override T pop(); @Override T peek(); boolean hasNext(); boolean hasRoom(); int getStackDepth(); static final int DEFAULT_INITIAL; }
@Test public void testHasNext() { ss.push(null); assertEquals(1, ((MyStack<String>) ss).getStackDepth()); assertTrue(((MyStack<String>) ss).hasNext()); }