Salient Soft

This simple example was performed with Eclipse Galileo 3.5.1

1/ Project Creation Dialog

From the menus in eclipse, select File/New/EJB project. On the resulting dialog, name the project. You can pick other options at this stage such as EAR membership but this can be done later if desired. Note that we are not amending the configuration section (via the modify button) at this stage to add JPA faceting (more on this later).

Click Finish and your EJB project will be created.

2/Project Facets

Right click your new project, and select Project Facets on the left. Tick the box marked Java Persistence in the middle pane, and you will be presented with the following screen :-

3/ JPA Facets

Now Click the “Further configuration available” link at the bottom. This will display the JPA Facet dialog as follows. On this screen you should do the following :-

1. Select the correct platform version and library type – typically these will be Eclipselink 1.1 or later version if available.
2. Untick the box marked “Include libraries with this application”.  The  latest Eclipselink.jar  library should be deployed separately to Glassfish, and stored in the $GLASSFISH_HOME/lib directory. To clarify, Eclipselink is available as a single jar, non-OSGI deployment, or split up into multiple jars for OSGI deployment. The OSGI jars have the long names with the OSGI packaging prefixes such as “org.eclipse.persistence.core” followed by name and version number information. They are a finer grained breakdown of the classes to allow more selectivity/flexibility in use. You can copy the OSGI jars to $GLASSFISH_HOME/lib directory – this will also work but is unnecessarily complex for non-OSGI use. This post here contains a brief overview of OSGI and links to detailed information about it.
3. Select the database connection to be used. If it is not already present, click the Add connection link to create a new one. This also allows you to add a new JDBC provider for a given database type, and point to the jar file(s) for the provider. Note that you will also need to add the JDBC provider jar to GLASSFISH_HOME/lib. To clarify, this database connection is used by eclipse to validate the persistent entities and mappings in the project during development. It is not used by Glassfish at run time. The run time connection (data source) will be created in Glassfish, and persistence.xml will be configured to use the datasource that you created in Glassfish.
4. Next, you can select whether your annotated persistent classes will be discovered automatically, or whether they must be listed explicitly in persistence.xml. To ensure portatbility, you should take the manual option as  automatic discovery is not guarrranteed to be portable.
5. Finally you can select whether or not to create orm.xml. You can always create it later if you need it – if you are using annotations entirely you won’t. This post here describes how you can combine both annotations and orm.xml in order to both take advantage of features like sequences in Oracle whilst still retaining database independance.

Click OK on the JPA Facet dialog, and then OK on the project facets screen. This will complete the creation of your project.

Note that as already stated, it is possible to click the modify button in the configuration section of the dialog in stage 1, which will also display the project facet screen. However, this version of the project facet screen is different to the one displayed if you select Project Facets after creating the project. In particular it does not have the “Further configuration available” option, and so does not allow you to display the JPA Facet dialog to modfy the options there. It assumes defaults for these options instead.

It is possible to  reconfigure the project JPA Facet settings subsequently, by selecting the “Java Persistence” option which appears in the list on the left of the project properties dialog (this only appears for projects with the JPA facet selected). This displays the “Java Persistence” dialog which has the same options as the “JPA Facets” dialog. Instead, you can also untick Java Persistence on the Project Facets screen, applying the changes, and retick the option. This will reveal the “Further Configuration Available” option to allow access to the JPA Facet dialog as well. In the example above, we added the Java persistence facet after saving the project which gave us immediate access to the JPA Facets dialog.

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