code: public com.google.api.CustomHttpPatternOrBuilder getCustomOrBuilder() {
      if (patternCase_ == 8) {
         return (com.google.api.CustomHttpPattern) pattern_;
      }
      return com.google.api.CustomHttpPattern.getDefaultInstance();
    }
docs: <pre>
  The custom pattern is used for specifying an HTTP method that is not
  included in the `pattern` field, such as HEAD, or "*" to leave the
  HTTP method unspecified for this rule. The wild-card rule is useful
  for services that provide content to Web (HTML) clients.
  </pre>
  
  <code>.google.api.CustomHttpPattern custom = 8;</code>