Goal

Add the ability to inject EntityManagers for a certain persistence unit in Eclipse 4.

Getting Started

Target platform - Repositories

First of all you have to get the Gemini JPA and Gemini DBAccess bundles to make this work. A sample target platform for Juno is available here.

The p2 repositories

• Gemini JPA 1.1.0
• Gemini DBAccess 1.1.0
• Gemini Ext Di

Inject it

You can directly inject an EntityManager via

@Inject
@GeminiPersistenceContext(unitName="puTest")
EntityManager em;

or you can inject an EntityManagerFactory if you want to have more control of your EntityManagers

@Inject
@GeminiPersistenceUnit(unitName="puTest")
EntityManager em;

Configuration

You can even configure your persistence units within the inject annotation.

@Inject
@GeminiPersistenceContext(unitName="puTest", properties = {
 @GeminiPersistenceProperty(name=PersistenceUnitProperties.JDBC_DRIVER, value="org.gjt.mm.mysql.Driver"),
 @GeminiPersistenceProperty(name=PersistenceUnitProperties.JDBC_URL, value="jdbc:mysql://127.0.0.1/test"),
 @GeminiPersistenceProperty(name=PersistenceUnitProperties.JDBC_USER, value="test"),
 @GeminiPersistenceProperty(name=PersistenceUnitProperties.JDBC_PASSWORD, value="test"))
})
EntityManager em;

even with the Preference annotation. If you don't know them take a look here

@Inject
@GeminiPersistenceContext(unitName = "unconfigured2", properties = {
  @GeminiPersistenceProperty(name = PersistenceUnitProperties.JDBC_DRIVER, valuePref = @Preference("jdbc_driver")),
  @GeminiPersistenceProperty(name = PersistenceUnitProperties.JDBC_URL, valuePref = @Preference("jdbc_url")) })
private EntityManager em;

Sample application

A complete sample application can be found here. It contains examples for

• Statically injected contexts
• Dynamically injected contextes
• Handling changing preferences with DAOs

Note

This repository contains the work done by Filipp A. and Nepomuk Seiler. See Gemini Forum Post for more information.