How do you harness URL external application in a JSP?

Question

I have successfully deployed the Yahoo Finance sample URL External Application. However, I do not understand how to utilize the URL classes (in the pdkjava.jar) to harness the external application information once a user has authenticated. I am building a JSP portlet that displays and applet, however the applet requires a username and password. I need to get the Username and Password from external application, which it gets from the user via External Application. How do I get these values in my JSP (that is defined in my provider.xml)? I keep seeing documentation regarding the ExternalPrincipal object however I don't understand how to utilize this object in my JSP. I beleive the ExternalPrincipal object is what I need in my JSP, seeing that it has the methods for getting the user and password. Unless is there a better way of achieving this, can anyone shed some light on getting the ExternalPrincipal object for an External Application session?
Thanks,
Laith E.H.

Answer 1

Thanks for the example. I have a better understanding now, however I'm still having trying to comprehend the flow of executing in this portal model.
I have a problem with:
PortletRenderRequest pr = (PortletRenderRequest) request.getAttribute("oracle.portal.PortletRenderRequest");
ProviderUser prUser = pr.getUser();
ProviderSession pSession = prUser.getSession(true);
I get a NullPointerException on the second line when trying to getUser(). I'm not sure where the problem could be. In the provider.xml, my ExternalProviderInstance, or the JSP itself? I have another JSP portlet on the same page that calls the same method with success.
Thanks,
Laith E.H.
provider.xml:
<?xml version="1.0" encoding="UTF-8"?>
<?providerDefinition version="3.1"?>
<provider class="oracle.portal.provider.v2.http.URLProviderDefinition">
     <providerInstanceClass>com.cox.portal.provider.ExternalProviderInstance</providerInstanceClass>
     <session>true</session>
     <authentication class="oracle.portal.provider.v2.security.Authentication">
          <authType>ExternalApp</authType>
          <userFieldName>Username</userFieldName>
          <userPwdName>Password</userPwdName>
          <errorPageMessages>Invalid ID,Invalid Password</errorPageMessages>
     </authentication>
     <portlet class="oracle.portal.provider.v2.http.URLPortletDefinition">
     <id>1</id>
     <name>ExternalAnalyzer</name>
     <title>Main Analyzer</title>
     <description>This portlet logs into analyzer</description>
     <timeout>100</timeout>
     <timeoutMessage>analyzer timed out</timeoutMessage>
          <showEdit>false</showEdit>
          <showEditDefault>false</showEditDefault>
          <showPreview>false</showPreview>
          <showDetails>false</showDetails>
          <hasHelp>false</hasHelp>
          <hasAbout>false</hasAbout>
          <acceptContentType>text/html</acceptContentType>
          <registrationPortlet>false</registrationPortlet>
          <accessControl>registered</accessControl>
          <renderer class="oracle.portal.provider.v2.render.RenderManager">
               <showPage class="oracle.portal.provider.v2.render.http.URLRenderer">
                    <pageUrl>http://catl0dv31.corp.cox.com/bic/analyzerIFrame.jsp?ap_doc=analyzer&amp;ap_id=105</pageUrl>
                    <contentType>text/html</contentType>
               </showPage>
          </renderer>
          <securityManager class="oracle.portal.provider.v2.security.URLSecurityManager">
               <authorizType>registered</authorizType>
          </securityManager>
     </portlet>
</provider>
ExternalProviderInstance:
package com.cox.portal.provider;
import oracle.portal.provider.v2.*;
import oracle.portal.provider.v2.http.*;
import oracle.portal.provider.v2.externalApp.*;
public class ExternalProviderInstance extends URLProviderInstance
public static final String EXTERNAL_APP = "externalapp.object.key";
ProviderSession pSession = null;
public Object[] initSession(ProviderUser user, ExternalPrincipal externalApp)
throws ProviderException {
//UrlServicesUtils.logMessage("BasicURLProvider : Entering initSession.", getDebugLevel());
//Create/Retrieve provider user session.
if (mProviderDefinition.getHasSession()) {
// Create the session if it doesn't already exist.
pSession = user.getSession(true);
// Store external app in provider session so that other modules
// can extract it later.
if (pSession != null) {
pSession.setAttribute(EXTERNAL_APP, externalApp);
// Get javax.servlet.http.Cookie[] from user
javax.servlet.http.Cookie[] cookies = ((ServletProviderUser)user).getCookies();
if(cookies != null)
return cookies;
else
return null;