### Question:
ApolloCertificate extends CertBase { public boolean isValid(Date date) { boolean dateOK = false; Date start = certificate.getNotBefore(); Date end = certificate.getNotAfter(); if (date != null && start != null && end != null) { if (date.after(start) && date.before(end)) { dateOK = true; } else { dateOK = false; } } return dateOK; } ApolloCertificate(X509Certificate certificate); static ApolloCertificate loadPEMFromPath(String path); static ApolloCertificate loadPEMFromStream(InputStream is); BigInteger getApolloId(); AuthorityID getAuthorityId(); String getCN(); String getOrganization(); String getOrganizationUnit(); String getCountry(); String getCity(); String getCertificatePurpose(); List<String> getIPAddresses(); List<String> getDNSNames(); String getStateOrProvince(); String getEmail(); String fromList(List<String> sl); List<String> fromString(String l); @Override String toString(); String getPEM(); boolean isValid(Date date); BigInteger getSerial(); CertAttributes getIssuerAttrinutes(); boolean verify();  }### Answer:
@Test public void testIsValid() { Date date = null; boolean expResult = false; boolean result = acert.isValid(date); assertEquals(expResult, result); }