You can use the following API to retrieve the Discovery Service bootstrap resource offering and included security token from the web services client:
ResourceOffering SAML2SDKUtil.getDiscoveryBootStrapResourceOffering( HttpServletRequest request) List SAML2SDKUtil.getDiscoveryBootStrapCredentials( HttpServletRequest request)
For more information, see the Sun OpenSSO Enterprise 8.0 Java API Reference.