From 71cc6576f6066be339a9d9b0bf766620a7750681 Mon Sep 17 00:00:00 2001
From: Project Nayuki <me@nayuki.io>
Date: Wed, 29 Nov 2017 20:35:41 +0000
Subject: [PATCH] Updated cache logic to be exception-safe.

---
 src/io/nayuki/fastqrcodegen/QrTemplate.java     | 17 +++++++++++------
 .../fastqrcodegen/ReedSolomonGenerator.java     | 17 +++++++++++------
 2 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/src/io/nayuki/fastqrcodegen/QrTemplate.java b/src/io/nayuki/fastqrcodegen/QrTemplate.java
index b60ce81..e218ed0 100644
--- a/src/io/nayuki/fastqrcodegen/QrTemplate.java
+++ b/src/io/nayuki/fastqrcodegen/QrTemplate.java
@@ -57,13 +57,18 @@ final class QrTemplate {
 			}
 		}
 		
-		QrTemplate tpl = new QrTemplate(version);
-		synchronized(cache) {
-			cache[version] = new SoftReference<>(tpl);
-			isPending[version] = false;
-			cache.notifyAll();
+		try {
+			QrTemplate tpl = new QrTemplate(version);
+			synchronized(cache) {
+				cache[version] = new SoftReference<>(tpl);
+			}
+			return tpl;
+		} finally {
+			synchronized(cache) {
+				isPending[version] = false;
+				cache.notifyAll();
+			}
 		}
-		return tpl;
 	}
 	
 	
diff --git a/src/io/nayuki/fastqrcodegen/ReedSolomonGenerator.java b/src/io/nayuki/fastqrcodegen/ReedSolomonGenerator.java
index 2a35fce..3ad23f1 100644
--- a/src/io/nayuki/fastqrcodegen/ReedSolomonGenerator.java
+++ b/src/io/nayuki/fastqrcodegen/ReedSolomonGenerator.java
@@ -59,13 +59,18 @@ final class ReedSolomonGenerator {
 			}
 		}
 		
-		ReedSolomonGenerator rs = new ReedSolomonGenerator(degree);
-		synchronized(cache) {
-			cache[degree] = new SoftReference<>(rs);
-			isPending[degree] = false;
-			cache.notifyAll();
+		try {
+			ReedSolomonGenerator rs = new ReedSolomonGenerator(degree);
+			synchronized(cache) {
+				cache[degree] = new SoftReference<>(rs);
+			}
+			return rs;
+		} finally {
+			synchronized(cache) {
+				isPending[degree] = false;
+				cache.notifyAll();
+			}
 		}
-		return rs;
 	}