How to declare Entities on the fly?
I try to develop a Java Plugin application using the Java plugin framework. All plugins will have acces to a uniq database using JPA (with Eclipselink).
But each plugin will have there own Entities.
So I could not declare all Enti开发者_如何转开发ties in one unique file persitence.xml in the core plugin.
The question is: is it possible to declare Entity class on the fly when declaring the EntityManagerFactory? I am already using a Map to get connection string and user/password from user configuration file.
Is there a way to do the same with Entities ?
Map<String, String> p = new HashMap<String, String>();
p.put("javax.persistence.jdbc.url", dns);
p.put("javax.persistence.jdbc.driver", "com.mysql.jdbc.Driver");
p.put("javax.persistence.jdbc.user", config.getProperty("com.cjrf.xbmo.db.username", ""));
p.put("javax.persistence.jdbc.password", config.getProperty("com.cjrf.xbmo.db.password", ""));
entityManagerFactory = Persistence.createEntityManagerFactory("mediamanager", p);
Thanks for your help.
This might help:
http://www.dynamicjava.org/projects/dynamic-jpa
If your only concern is not do declare the class files in the persistence.xml then you can use auto detect funcionality.
For eclipselink add this to persistence.xml
<exclude-unlisted-classes>false</exclude-unlisted-classes>
Now all annotation mapped with @Entity
will be scanned automatically.
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