title: Way to design app that uses http requests
body: <p>In my app I have, for example, 3 logical blocks, created by user in such order:</p>
  
  <p>FirstBlock -> SecondBlock -> ThirdBlock</p>
  
  <p>This is no class-inheritance between them (each of them <strong>doesn't</strong> extends any other), but logical-inheritance exists (for example <code>Image</code> contains <code>Area</code> contains <code>Message</code>). Sorry, I'm not strong in terms - hope you'll understand me.</p>
  
  <p>Each of blocks sends requests to server (to create infromation about it on server side) and then handles responses independently (but using same implementation of http client). Just like at that image (red lines are responses, black - requests).</p>
  
  <p><a href="http://s2.ipicture.ru/uploads/20120121/z56Sr62E.png" rel="nofollow noreferrer">http://s2.ipicture.ru/uploads/20120121/z56Sr62E.png</a></p>
  
  <p><strong>Question</strong>
  Is it good model? Or it's better to create a some controller-class, that will send requests by it's own, and then handle responses end redirect results to my blocks? Or should implementation of http client be controller itself?</p>
  
  <p><strong>P.S.</strong> If I forgot to provide some information - please, tell me. Also if there a errors in my English - please, edit question.</p>