CryptoPrimitives implements CryptoSuite { public byte[] certificateToDER(String certificatePEM) { byte[] content = null; try (PemReader pemReader = new PemReader(new StringReader(certificatePEM))) { final PemObject pemObject = pemReader.readPemObject(); content = pemObject.getContent(); } catch (IOException e) { } return content; } CryptoPrimitives(); Certificate bytesToCertificate(byte[] certBytes); PrivateKey bytesToPrivateKey(byte[] pemKey); @Override boolean verify(byte[] pemCertificate, String signatureAlgorithm, byte[] signature, byte[] plainText); KeyStore getTrustStore(); void addCACertificateToTrustStore(File caCertPem, String alias); void addCACertificateToTrustStore(byte[] bytes, String alias); @Override void loadCACertificates(Collection<Certificate> certificates); @Override void loadCACertificatesAsBytes(Collection<byte[]> certificatesBytes); @Override KeyPair keyGen(); @Override byte[] sign(PrivateKey key, byte[] data); String generateCertificationRequest(String subject, KeyPair pair); @Override byte[] hash(byte[] input); @Override CryptoSuiteFactory getCryptoSuiteFactory(); void init(); @Override Properties getProperties(); byte[] certificateToDER(String certificatePEM);  }
@Test public void testCertificateToDER() throws Exception { KeyPair testKeyPair = crypto.keyGen(); String certRequest = crypto.generateCertificationRequest("common name", testKeyPair); Assert.assertTrue(crypto.certificateToDER(certRequest).length > 0); }