### Question:
RequestSigningService { public TppSignatureCertificate buildTppSignatureCertificate() { return TppSignatureCertificate.builder() .publicKeyAsString(getPublicKeyAsString()) .build(); } RequestSigningService(Pkcs12KeyStore keyStore); Digest buildDigest(String requestBody); Signature buildSignature(Map<String, String> headersMap); TppSignatureCertificate buildTppSignatureCertificate();  }### Answer:
@Test void buildTppSignatureCertificate() throws KeyStoreException, UnsupportedEncodingException, CertificateException { when(keyStore.getQsealCertificate()).thenReturn(certificate); TppSignatureCertificate actual = service.buildTppSignatureCertificate(); verify(keyStore, times(1)).getQsealCertificate(); assertNotNull(actual); assertEquals(RequestHeaders.TPP_SIGNATURE_CERTIFICATE, actual.getHeaderName()); assertTrue(actual.getHeaderValue().contains("MIIBLTCB2KADAgECAgEDMA0GCSqGSI")); }