How to invoke another OSGI bundle servlet from different OSGI bundle?

I got this use case to work. The following pic shows an AEM web page that displays data returned from a Sling Servlet (the Sling Servlet invoked by an AEM Service):

[img]SlingInvoke.png[/img]

Here is the community article that steps you through this use case:

https://helpx.adobe.com/experience-manager/using/HttpClient_AEM.html

Only use this use case if you have to invoke a servlet from a service. It better to invoke the servlet from a web page using AJAX - as talked about here:

http://helpx.adobe.com/experience-manager/using/custom-sling-servlets.html