From 2fe3da506e8bfff1739b4ddf1fc1756541aab941 Mon Sep 17 00:00:00 2001
From: Gustavo Martin Morcuende <gu.martinm@gmail.com>
Date: Fri, 29 Jul 2016 20:09:44 +0200
Subject: [PATCH] Explanation about Spring overriding beans when running JUnit
 tests

---
 .../src/test/resources/datasource-test-configuration.xml         | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/SpringJava/JPA/spring-jpa-persistence/src/test/resources/datasource-test-configuration.xml b/SpringJava/JPA/spring-jpa-persistence/src/test/resources/datasource-test-configuration.xml
index 8ad0406..68cd61f 100644
--- a/SpringJava/JPA/spring-jpa-persistence/src/test/resources/datasource-test-configuration.xml
+++ b/SpringJava/JPA/spring-jpa-persistence/src/test/resources/datasource-test-configuration.xml
@@ -22,6 +22,15 @@
     <jdbc:embedded-database id="dataSource" type="H2" />
 	-->
 	
+	<!-- 
+		1. There are two beans with the same id "dataSource"
+		   One declared in datasource-configuration.xml
+		   Another one declared in datasource-test-configuration.xml
+		2. Both beans are declared in different XML files.
+		3. Because there are in different XML files Spring does not complain about having duplicate beans.
+		4. Because files in src/test will be loaded in class path after files in src/main this bean will
+		   override the one declared in datasource-configuration.xml when running JUnit Tests :)
+	 -->
 	<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
 		<property name="driverClassName" value="org.h2.Driver" />
 		<property name="url" value="jdbc:h2:mem:mybatis_example;INIT=create schema if not exists mybatis_example\;SET SCHEMA mybatis_example;MODE=DB2;DB_CLOSE_DELAY=-1;DB_CLOSE_ON_EXIT=FALSE" />
-- 
2.1.4