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<h1>Cocoon and continuations</h1>
  
<p>With continuations in the language, you can essentially
  store the continuation of <span class="codefrag">sendPageAndWait()</span> (think of all
  the stack trace, and the program counter), put it in a global
  hash table associated with an id. The id is then encoded in
  the <span class="codefrag">response.xml</span> page as an URL. When the user
  clicks on that URL, on the server side the associated
  continuation is resumed. Resuming the processing happens as if
  nothing was stopped, you get all the stack trace back, and all
  the local variables.</p>

  
<p>So instead of using beans to store things in session, you
  use normal variables in a program. Since each user has its own
  version of the program, all the local variables in the program
  are separate between users.</p>

  
<p>With this approach clicking the <em>Back</em> button in the
  browser is no longer a hassle to deal with for you as a
  server-side programmer. They will simply refer to past
  continuations objects, which have their own state of the local
  variables.</p>

  
<p>Since continuations are objects, you can also store them in
  a database, for really long-lived session, just like you do
  with session beans.</p>
  

  
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