title: HTTP Request without using Browser
body: <p>I am working on a application which allows user to download JARs which is actually a PDF player displaying some PDFs which are downloaded as a part of JAR itself. </p>
  
  <p>Now whenever users clicks on that JAR File, I want to validate the PDF Bundle on the server (whether it got expired? Or a new version is available). Also, I want my PDF Content to get updated if a new version of the downloaded bundle is available. So I will need to download the PDFs from the server if a new version is there.</p>
  
  <p>So I want to make a HTTP Request to the server from inside my JAR &amp; receive some PDFs (and some additional data as well) as response. </p>
  
  <p>Any idea how I can do this? Is there some API available for creating HTTP Requests from a plain Java Program?</p>