openxava / documentation / Configuration for MySQL

Configuring your OpenXava application to go against MySQL is very simple, basically you have to install the JDBC driver for MySQL and define correctly the datasource. You don't need to touch any code of your application.
We assume you have already installed and running MySQL.

Download the JDBC driver for MySQL

Download the MySQL driver from here: https://dev.mysql.com/downloads/connector/j/

You will download a file like this: mysql-connector-java-8.0.17.zip (the version numbers may vary). Uncompress it to find inside a file called mysql-connector-java-8.0.17.jar (or so), this last file, the .jar, is the JDBC controller we're going to use.

Create a classpath variable in Eclipse

In order you can connect to MySQL from Eclipse we're going to declare a classpath variable that points to the MySQL JDBC driver, so you can use it in any project you need easily. For that, in Eclipse go to Window > Preferences > Java > Build Path > Classpath Variables where you can add the new variable:
You can call the variable MYSQL_DRIVER instead of DB_DRIVER if your prefer. The path is the path of the JDBC driver, in our case the path of mysql-connector-java-8.0.17.jar we have just downloaded.

Add the DB_DRIVER variable to your Eclipse project

In the project you're going to use MySQL you have to add the variable declared above. Click with right mouse button on your project and then choose Java Build Path > Configure Build Path...:
project-build-path-eclipse-menu_en.png
Then select the Libraries tab:
With this we have the driver available for the development environment.

Add the JDBC driver to the production Tomcat

Adding the driver in production is much easier. Copy mysql-connector-java-8.0.17.jar to the lib folder of your Tomcat. Done.

Adjust your datasource definition

For development edit web/META-INF/context.xml of your Eclipse project, and for production edit conf/context.xml of your Tomcat to adjust the datasource to point to MySQL, something like this:
<Resource name="jdbc/MyAppDS" auth="Container"
	type="javax.sql.DataSource"
	maxTotal="100" maxIdle="20" maxWaitMillis="10000"
	username="root" password="ao49fmsk"
	driverClassName="com.mysql.jdbc.Driver"
	url="jdbc:mysql://localhost:3306/"/>
The differences are the driverClassName and the url. Obviously, instead of localhost you should put the address of the server that hosts MySQL, and also put the correct username and password.

Update persistence.xml

In the default persistence unit of persistence.xml (in persistence/META-INF) you have to change the hibernate.default_schema property by hibernate.default_catalog. Also, if you use hibernate.dialect property just remove it.
<persistence-unit name="default">
	<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
	<non-jta-data-source>java://comp/env/jdbc/MyAppDS</non-jta-data-source>
	<class>org.openxava.session.GalleryImage</class>
	<class>org.openxava.web.editors.DiscussionComment</class>
	<properties>
		<property name="javax.persistence.schema-generation.database.action" value="update"/>
		<property name="javax.persistence.create-database-schemas" value="true"/> 
		<property name="hibernate.default_catalog" value="myappdb"/>
		<property name="hibernate.jdbc.use_streams_for_binary" value="true"/>
	</properties>
</persistence-unit>
Note as we use hibernate.default_catalog to indicate your MySQL database, myappdb in this case.
Morever, you have to modify the junit persistence unit to point to MySQL.
<!-- JUnit MySQL -->
<persistence-unit name="junit">
	<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
	<class>org.openxava.web.editors.DiscussionComment</class>
	<properties>
		<property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/>
		<property name="hibernate.connection.username" value="root"/>
		<property name="hibernate.connection.password" value="ao49fmsk"/>		
		<property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/myappdb"/>
	</properties>
</persistence-unit>
Adapt the username, password and url to your MySQL configuration.