/**
  * Creates a SAML Assertion that can be used as a bearer token when invoking REST services. The
  * REST service must be configured to accept SAML Assertion bearer tokens.
  *
  * <p>In JBoss this means protecting the REST services with {@link SAMLBearerTokenLoginModule}. In
  * Tomcat7 this means protecting the REST services with {@link SAMLBearerTokenAuthenticator}.
  *
  * @param issuerName the issuer name (typically the context of the calling web app)
  * @param forService the web context of the REST service being invoked
  */
 public static String createSAMLAssertion(String issuerName, String forService) {
   if (isJBoss7()) {
     return Jboss7SAMLBearerTokenUtil.createSAMLAssertion(issuerName, forService);
   }
   if (isTomcat()) {
     return TomcatSAMLBearerTokenUtil.createSAMLAssertion(
         HttpRequestThreadLocalValve.TL_request.get(), issuerName, forService);
   }
   throw new RuntimeException("Unsupported/undetected platform.");
 }
 /** Determines if we're running in tomcat. */
 private static boolean isTomcat() {
   if (HttpRequestThreadLocalValve.TL_request.get() != null) {
     return true;
   }
   return false;
 }