Add JDBC documentation

Fixes gh-415

samples/httpsession-jdbc-xml/src/main/webapp/WEB-INF/spring/session.xml

@@ -14,7 +14,7 @@
 	<bean class="org.springframework.session.jdbc.config.annotation.web.http.JdbcHttpSessionConfiguration"/>
 
 	<!--2-->
-	<jdbc:embedded-database id="dataSource" type="H2">
+	<jdbc:embedded-database id="dataSource" database-name="testdb" type="H2">
 		<jdbc:script location="classpath:org/springframework/session/jdbc/schema-h2.sql"/>
 	</jdbc:embedded-database>
 

samples/httpsession-jdbc-xml/src/main/webapp/WEB-INF/web.xml

@@ -49,6 +49,16 @@
 		<url-pattern>/session</url-pattern>
 	</servlet-mapping>
 
+	<servlet>
+		<servlet-name>h2console</servlet-name>
+		<servlet-class>org.h2.server.web.WebServlet</servlet-class>
+	</servlet>
+
+	<servlet-mapping>
+		<servlet-name>h2console</servlet-name>
+		<url-pattern>/console/*</url-pattern>
+	</servlet-mapping>
+
 	<welcome-file-list>
 		<welcome-file>index.jsp</welcome-file>
 	</welcome-file-list>

samples/httpsession-jdbc/src/main/java/sample/H2ConsoleInitializer.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2014-2016 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package sample;
+
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+
+import org.h2.server.web.WebServlet;
+
+import org.springframework.web.WebApplicationInitializer;
+
+public class H2ConsoleInitializer implements WebApplicationInitializer {
+
+	@Override
+	public void onStartup(ServletContext servletContext) throws ServletException {
+		servletContext.addServlet("h2console", new WebServlet()).addMapping("/console/*");
+	}
+
+}