code: Key getPublicKey(String trustedAlias, String trustStoreRef, String signatureAlgorithm)
  			throws KeyStoreServiceException, KeyException {
  		Key signingKey = getPublicKeyFromKeystore(trustedAlias, trustStoreRef, signatureAlgorithm);
  		if (tc.isDebugEnabled()) {
  			Tr.debug(tc, "Trusted alias: " + trustedAlias + ", Truststore: " + trustStoreRef);
  			Tr.debug(tc, "RSAPublicKey: " + (signingKey instanceof RSAPublicKey));
  		}
  		if (signingKey != null && !(signingKey instanceof RSAPublicKey)) {
  			signingKey = null;
  		}
  		return signingKey;
  	}
docs: Creates a Key object from the certificate stored in the trust store and alias
  provided.