code: public static PublicKey getPublicKey(final PKCS10CertificationRequest csr)
              throws IOException {
  		SubjectPublicKeyInfo pkInfo = csr.getSubjectPublicKeyInfo();
  		JcaPEMKeyConverter converter = new JcaPEMKeyConverter();
  		return converter.getPublicKey(pkInfo);
      }
docs: Extracts the <tt>PublicKey</tt> from the provided CSR.
  <p>
  This method will throw a {@link RuntimeException} if the JRE is missing
  the RSA algorithm, which is a required algorithm as defined by the JCA.
  
  @param csr
  the CSR to extract from.
  @return the extracted <tt>PublicKey</tt>
  @throws IOException
  if there is an error extracting the <tt>PublicKey</tt>
  parameters.