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copied!<p>Have a look at <a href="http://onpersistence.blogspot.com/2010/03/running-sql-script-on-startup-in.html" rel="noreferrer">Running a SQL Script on startup in EclipseLink</a> that describes a solution presented as a kind of equivalent to Hibernate's <code>import.sql</code> feature<sup>1</sup>. Credits to Shaun Smith:</p> <blockquote> <h2><a href="http://onpersistence.blogspot.com/2010/03/running-sql-script-on-startup-in.html" rel="noreferrer">Running a SQL Script on startup in EclipseLink</a></h2> <p>Sometimes, when working with DDL generation it's useful to run a script to clean up the database first. In Hibernate if you put a file called "import.sql" on your classpath its contents will be sent to the database. Personally I'm not a fan of magic filenames but this can be a useful feature.</p> <p>There's no built in support for this in EclipseLink but it's easy to do thank's to EclipseLink's high extensibility. Here's a quick solution I came up with: I simply register an event listener for the session postLogin event and in the handler I read a file and send each SQL statement to the database--nice and clean. I went a little further and supported setting the name of the file as a persistence unit property. You can specify this all in code or in the persistence.xml.</p> <p>The <code>ImportSQL</code> class is configured as a <code>SessionCustomizer</code> through a persistence unit property which, on the <code>postLogin</code> event, reads the file identified by the "import.sql.file" property. This property is also specified as a persistence unit property which is passed to <code>createEntityManagerFactory</code>. This example also shows how you can define and use your own persistence unit properties.</p> <pre><code>import org.eclipse.persistence.config.SessionCustomizer; import org.eclipse.persistence.sessions.Session; import org.eclipse.persistence.sessions.SessionEvent; import org.eclipse.persistence.sessions.SessionEventAdapter; import org.eclipse.persistence.sessions.UnitOfWork; public class ImportSQL implements SessionCustomizer { private void importSql(UnitOfWork unitOfWork, String fileName) { // Open file // Execute each line, e.g., // unitOfWork.executeNonSelectingSQL("select 1 from dual"); } @Override public void customize(Session session) throws Exception { session.getEventManager().addListener(new SessionEventAdapter() { @Override public void postLogin(SessionEvent event) { String fileName = (String) event.getSession().getProperty("import.sql.file"); UnitOfWork unitOfWork = event.getSession().acquireUnitOfWork(); importSql(unitOfWork, fileName); unitOfWork.commit() } }); } </code></pre> <hr> <pre><code>public static void main(String[] args) { Map<String, Object> properties = new HashMap<String, Object>(); // Enable DDL Generation properties.put(PersistenceUnitProperties.DDL_GENERATION, PersistenceUnitProperties.DROP_AND_CREATE); properties.put(PersistenceUnitProperties.DDL_GENERATION_MODE, PersistenceUnitProperties.DDL_DATABASE_GENERATION); // Configure Session Customizer which will pipe sql file to db before DDL Generation runs properties.put(PersistenceUnitProperties.SESSION_CUSTOMIZER, "model.ImportSQL"); properties.put("import.sql.file","/tmp/someddl.sql"); EntityManagerFactory emf = Persistence .createEntityManagerFactory("employee", properties); } </code></pre> </blockquote> <p>I'm not sure it's a strict equivalent though, I'm not sure the script will run after the database generation. Testing required. If it doesn't, maybe it can be adapted.</p> <p><sub><sup>1</sup> Hibernate has a neat little feature that is heavily under-documented and unknown. You can execute an SQL script during the SessionFactory creation right after the database schema generation to import data in a fresh database. You just need to add a file named import.sql in your classpath root and set either create or create-drop as your hibernate.hbm2ddl.auto property.</sub></p>

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