From 0b45bda64516af36577e6c72e2a0175a2f51701d Mon Sep 17 00:00:00 2001
From: Peter Wu <peter@lekensteyn.nl>
Date: Wed, 11 Jun 2014 15:05:55 +0200
Subject: getBrands: Fix hang when done

For producer thread 0 and consumer threads 1 and 2

 0:queue size = 0
 1:get(); hangs...
 2:get(); hangs...
 0:put suicide pill
 1:get resumes, exits

Observe that 2:get is still running (deadlocks). To "fix" this, add
multiple suicide pills. The current value (16) allows up to 16
concurrent workers.
---
 src/database/BrandAnalyzerQueue.java | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/database/BrandAnalyzerQueue.java b/src/database/BrandAnalyzerQueue.java
index f6b0a40..af5ba7c 100644
--- a/src/database/BrandAnalyzerQueue.java
+++ b/src/database/BrandAnalyzerQueue.java
@@ -42,7 +42,10 @@ public class BrandAnalyzerQueue implements Runnable {
         }
         try {
             last = true;
-            queue.put(new Result(-1, null));
+            // for each concurrent worker, there must be at least one killer
+            for (int i = 0; i < 16; i++) {
+                queue.put(new Result(-1, null));
+            }
         } catch (InterruptedException ex) {
             getLogger().log(Level.SEVERE, "Failed to insert suicide pill!");
         }
-- 
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