From c1db200c546e3318d436876efc68b613a01b00a7 Mon Sep 17 00:00:00 2001
From: Athou <jeremiepanzer@gmail.com>
Date: Sun, 21 Apr 2013 11:24:45 +0200
Subject: [PATCH] move write lock to feed creation only

---
 .../backend/services/FeedService.java         | 31 +++++++++++++++++++
 .../services/FeedSubscriptionService.java     | 20 +++---------
 2 files changed, 35 insertions(+), 16 deletions(-)
 create mode 100644 src/main/java/com/commafeed/backend/services/FeedService.java

diff --git a/src/main/java/com/commafeed/backend/services/FeedService.java b/src/main/java/com/commafeed/backend/services/FeedService.java
new file mode 100644
index 00000000..06c17daa
--- /dev/null
+++ b/src/main/java/com/commafeed/backend/services/FeedService.java
@@ -0,0 +1,31 @@
+package com.commafeed.backend.services;
+
+import javax.ejb.Lock;
+import javax.ejb.LockType;
+import javax.ejb.Singleton;
+import javax.inject.Inject;
+
+import org.apache.commons.codec.digest.DigestUtils;
+
+import com.commafeed.backend.dao.FeedDAO;
+import com.commafeed.backend.model.Feed;
+
+@Singleton
+public class FeedService {
+
+	@Inject
+	FeedDAO feedDAO;
+
+	@Lock(LockType.WRITE)
+	public Feed findOrCreate(String url) {
+		Feed feed = feedDAO.findByUrl(url);
+		if (feed == null) {
+			feed = new Feed();
+			feed.setUrl(url);
+			feed.setUrlHash(DigestUtils.sha1Hex(url));
+			feedDAO.save(feed);
+		}
+		return feed;
+	}
+
+}
diff --git a/src/main/java/com/commafeed/backend/services/FeedSubscriptionService.java b/src/main/java/com/commafeed/backend/services/FeedSubscriptionService.java
index f1de5767..6a25b661 100644
--- a/src/main/java/com/commafeed/backend/services/FeedSubscriptionService.java
+++ b/src/main/java/com/commafeed/backend/services/FeedSubscriptionService.java
@@ -2,14 +2,9 @@ package com.commafeed.backend.services;
 
 import java.util.List;
 
-import javax.ejb.Lock;
-import javax.ejb.LockType;
-import javax.ejb.Singleton;
+import javax.ejb.Stateless;
 import javax.inject.Inject;
 
-import org.apache.commons.codec.digest.DigestUtils;
-
-import com.commafeed.backend.dao.FeedDAO;
 import com.commafeed.backend.dao.FeedEntryDAO;
 import com.commafeed.backend.dao.FeedEntryStatusDAO;
 import com.commafeed.backend.dao.FeedSubscriptionDAO;
@@ -21,11 +16,11 @@ import com.commafeed.backend.model.FeedSubscription;
 import com.commafeed.backend.model.User;
 import com.google.api.client.util.Lists;
 
-@Singleton
+@Stateless
 public class FeedSubscriptionService {
 
 	@Inject
-	FeedDAO feedDAO;
+	FeedService feedService;
 
 	@Inject
 	FeedEntryDAO feedEntryDAO;
@@ -36,17 +31,10 @@ public class FeedSubscriptionService {
 	@Inject
 	FeedSubscriptionDAO feedSubscriptionDAO;
 
-	@Lock(LockType.WRITE)
 	public Feed subscribe(User user, String url, String title,
 			FeedCategory category) {
 
-		Feed feed = feedDAO.findByUrl(url);
-		if (feed == null) {
-			feed = new Feed();
-			feed.setUrl(url);
-			feed.setUrlHash(DigestUtils.sha1Hex(url));
-			feedDAO.save(feed);
-		}
+		Feed feed = feedService.findOrCreate(url);
 
 		FeedSubscription sub = feedSubscriptionDAO.findByFeed(user, feed);
 		boolean newSubscription = false;