From: Bill Erickson <berickxx@gmail.com>
Date: Thu, 1 Dec 2016 17:22:40 +0000 (-0500)
Subject: LP#1646166 Hatch Java docs continued
X-Git-Url: https://old-git.evergreen-ils.org/?a=commitdiff_plain;h=f1f87b375b26c8a4f93fca0b797e621437fe4fea;p=working%2FHatch.git

LP#1646166 Hatch Java docs continued

Signed-off-by: Bill Erickson <berickxx@gmail.com>
---

diff --git a/src/org/evergreen_ils/hatch/Hatch.java b/src/org/evergreen_ils/hatch/Hatch.java
index 9a8759b9fa..8773fc6f9b 100644
--- a/src/org/evergreen_ils/hatch/Hatch.java
+++ b/src/org/evergreen_ils/hatch/Hatch.java
@@ -34,7 +34,32 @@ import java.util.concurrent.LinkedBlockingQueue;
 /**
  * Main class for Hatch.
  *
- * TODO
+ * Data flow:
+ *
+ * 1. MessageIO::MessageReader thread reads messages on STDIN and queues
+ *    them for later processing by the RequestHandler thread.
+ *
+ * 2. RequestHandler thread collects and unpacks the request for processing.
+ *
+ * 2a. Non-print requests (e.g. file IO) are handled within the 
+ *     RequestHandler thread.
+ *
+ * 2a1. RequestHandler puts responses into the MessageIO::MessageWriter
+ *      outbound message queue.
+ *
+ * 2b. Print requests are added to the Hatch print request queue.
+ * 
+ * 2b1. The PrintRequestShuffler thread passes print requests from the
+ *      print request queue to the FX thread for future processing.
+ *
+ * 2b2. The FX thread renders and prints the HTML
+ *
+ * 2b3. The FX thread puts responses into the MessageIO::MessageWriter
+ *      outbound message queue (via PrintManager) once printing is 
+ *      complete.
+ *
+ * 3. MessageIO::MessageWriter pulls messages from the outbound queue
+ *    and writes them to STDOUT.
  *
  * Beware: On Mac OS, the "FX Application Thread" is renamed to 
  * "AppKit Thread" when the first call to print() or showPrintDialog()