### Question:
NeutronCacheEntry implements Serializable { public boolean isExpired() { if (expires == null) { return true; } return System.currentTimeMillis() > expires.getTimeInMillis(); } NeutronCacheEntry(String neutronUrl, String token, Calendar expires); String getNeutronUrl(); void setNeutronUrl(String neutronUrl); String getToken(); void setToken(String token); boolean isExpired();  }### Answer:
@Test public void isExpiredTrueTest() { Calendar expires = new GregorianCalendar(2013, 0, 31); NeutronCacheEntry neutronCacheEntry = new NeutronCacheEntry(NEUTRON_URL, TOKEN, expires); assertTrue(neutronCacheEntry.isExpired()); }
@Test public void isExpiredFalseTest() { Calendar expires = new GregorianCalendar(2100, 0, 31); NeutronCacheEntry neutronCacheEntry = new NeutronCacheEntry(NEUTRON_URL, TOKEN, expires); assertFalse(neutronCacheEntry.isExpired()); }
@Test public void isExpiredNullTest() { Calendar expires = null; NeutronCacheEntry neutronCacheEntry = new NeutronCacheEntry(NEUTRON_URL, TOKEN, expires); assertTrue(neutronCacheEntry.isExpired()); }