code: @Override
      public CertPathBuilderResult engineBuild(CertPathParameters params)
          throws CertPathBuilderException, InvalidAlgorithmParameterException {
  
          if (debug != null) {
              debug.println("SunCertPathBuilder.engineBuild(" + params + ")");
          }
  
          buildParams = PKIX.checkBuilderParams(params);
          return build();
      }
docs: Attempts to build a certification path using the Sun build
  algorithm from a trusted anchor(s) to a target subject, which must both
  be specified in the input parameter set. By default, this method will
  attempt to build in the forward direction. In order to build in the
  reverse direction, the caller needs to pass in an instance of
  SunCertPathBuilderParameters with the buildForward flag set to false.
  
  <p>The certification path that is constructed is validated
  according to the PKIX specification.
  
  @param params the parameter set for building a path. Must be an instance
  of <code>PKIXBuilderParameters</code>.
  @return a certification path builder result.
  @exception CertPathBuilderException Exception thrown if builder is
  unable to build a complete certification path from the trusted anchor(s)
  to the target subject.
  @throws InvalidAlgorithmParameterException if the given parameters are
  inappropriate for this certification path builder.