CookieCollection implements Collection<Cookie> { @Override public boolean contains(Object o) { if(o instanceof String) { return cookieMap.containsKey(o); } if(o instanceof Cookie) { return cookieMap.containsValue(o); } return false; } CookieCollection();  CookieCollection(Cookie... cookies);  CookieCollection(Collection<? extends Cookie> cookies); @Override int size(); @Override boolean isEmpty(); @Override boolean contains(Object o); @Override Iterator<Cookie> iterator(); Cookie [] toArray(); @Override T[] toArray(T[] ts); @Override boolean add(Cookie cookie); @Override boolean remove(Object o); Cookie get(String name); @Override boolean containsAll(Collection<?> collection); @Override boolean addAll(Collection<? extends Cookie> collection); @Override boolean removeAll(Collection<?> collection); @Override boolean retainAll(Collection<?> collection); @Override void clear();  }
@Test public void contains() throws Exception { CookieCollection cookies = new CookieCollection(cookie); Assert.assertTrue(cookies.contains(cookie)); Assert.assertTrue(cookies.contains(COOKIE_NAME)); Assert.assertFalse(cookies.contains("yuck")); }