code: private RequestProcessor findProcessorForExchange(HTTPExchange exch) {
          assertLocked();
  
          for (RequestProcessor reqProc : procThreads) {
              if (exch == reqProc.procExchange)
                  return reqProc;
          }
  
          return null;
      }
docs: Finds <tt>RequestProcessor</tt> which has claimed given exchange.
  
  @param exch the <tt>HTTPExchange</tt> for which <tt>RequestProcessor</tt>
  is to be found.
  
  @return <tt>{@link RequestProcessor}</tt> that has claimed given
  <tt>HTTPExchange</tt> or <tt>null</tt> if the exchange has not been
  claimed yet.