/**
  * 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
  * @param timeValidInMillis how long the saml assertion should be valid for (in milliseconds)
  */
 public static String createSAMLAssertion(
     String issuerName, String forService, int timeValidInMillis) {
   SAMLAssertionFactory factory = getSAMLAssertionFactory();
   if (factory == null) {
     throw new RuntimeException(
         "Failed to create SAML Assertion:  Unsupported/undetected platform."); //$NON-NLS-1$
   } else {
     return factory.createSAMLAssertion(issuerName, forService, timeValidInMillis);
   }
 }