From 9320b6beb86fbcf9f590495daba2a7f04a918130 Mon Sep 17 00:00:00 2001
From: Athou <jeremiepanzer@gmail.com>
Date: Wed, 13 Aug 2014 10:01:38 +0200
Subject: [PATCH] units of work can now be chained

---
 .../com/commafeed/backend/dao/UnitOfWork.java | 27 ++++++++++++-------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/src/main/java/com/commafeed/backend/dao/UnitOfWork.java b/src/main/java/com/commafeed/backend/dao/UnitOfWork.java
index 27f8d347..4c6e0f33 100644
--- a/src/main/java/com/commafeed/backend/dao/UnitOfWork.java
+++ b/src/main/java/com/commafeed/backend/dao/UnitOfWork.java
@@ -16,24 +16,31 @@ public abstract class UnitOfWork<T> {
 	protected abstract T runInSession() throws Exception;
 
 	public T run() {
-		final Session session = sessionFactory.openSession();
-		if (ManagedSessionContext.hasBind(sessionFactory)) {
-			throw new IllegalStateException("Already in a unit of work!");
-		}
+		boolean newSession = !ManagedSessionContext.hasBind(sessionFactory);
+
+		final Session session = newSession ? sessionFactory.openSession() : sessionFactory.getCurrentSession();
 		T t = null;
 		try {
-			ManagedSessionContext.bind(session);
-			session.beginTransaction();
+			if (newSession) {
+				ManagedSessionContext.bind(session);
+				session.beginTransaction();
+			}
 			try {
 				t = runInSession();
-				commitTransaction(session);
+				if (newSession) {
+					commitTransaction(session);
+				}
 			} catch (Exception e) {
-				rollbackTransaction(session);
+				if (newSession) {
+					rollbackTransaction(session);
+				}
 				this.<RuntimeException> rethrow(e);
 			}
 		} finally {
-			session.close();
-			ManagedSessionContext.unbind(sessionFactory);
+			if (newSession) {
+				session.close();
+				ManagedSessionContext.unbind(sessionFactory);
+			}
 		}
 		return t;
 	}