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In a project which I work on I don't use Spring, I use Hibernate only. I don't want to use hbm.xml files for entity mappings/descriptions/etc. I want to use annotations only.

How do I tell Hibernate to load all Entity/Table annotated classes from certain package(s)?

I searched on the web but I have no luck. Also I don't find information about the latest Hibernate version (mostly outdated articles/posts/etc.).

Edit 1:

http://docs.jboss.org/hibernate/orm/4.3/manual/en-US/html_single/#mapping

The hibernate doc page says this:

Object/relational mappings can be defined in three approaches:
1) using Java 5 annotations (via the Java Persistence 2 annotations)
2) using JPA 2 XML deployment descriptors (described in chapter XXX)
3) using the Hibernate legacy XML files approach known as hbm.xml

So that's it, I just want to use 1) with the SessionFactory/Session Hibernate API.

Edit 2:

Even though my questions was marked as duplicate, it's not, because I don't want to use JPA (and the implied descriptors) but just approach 1) from those listed above.

peter.petrov
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  • @hwellmann What if I don't want to have persistence.xml but only hibernate.cfg.xml? Do I need to have both? I just wanted hibernate.cfg.xml with the behavior of Hibernate scanning the annotated entity classes. Isn't that possible?! – peter.petrov Jan 23 '15 at 09:26
  • @VladMihalcea What if I don't want to have persistence.xml but only hibernate.cfg.xml? Do I need to have both? I just wanted hibernate.cfg.xml with the behavior of Hibernate scanning the annotated entity classes. Isn't that possible?! – peter.petrov Jan 23 '15 at 09:27
  • In other words I thought with those annotations in the entity classes, I can just avoid using .hbm.xml mapping files and still use the SessionFactory & Session APIs provided by Hibernate, and have these APIs know about my entity classes. Any ideas how to most easily achieve that? – peter.petrov Jan 23 '15 at 09:33
  • http://docs.jboss.org/hibernate/orm/4.3/manual/en-US/html_single/#mapping – peter.petrov Jan 23 '15 at 09:53
  • Anyway, my question is in no way duplicate to the question pointed out above. – peter.petrov Jan 23 '15 at 10:04

1 Answers1

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OK, this is not possible in Hibernate 4.3.x and was never possible it seems.

See also this question/answer (even though this post is old, it's quite valid):
Add Annotated Class in Hibernate by adding all classes in some package. JAVA

1) After I did some research on this, it seems it's a common misconception that Configuration.addPackage allows us to load all entity classes from a given package. It's not true. I found it the hard way by looking in the hibernate sources and only then I found the above SO question/answer which confirmed it. In fact I am not quite sure what addPackage does, but it doesn't seem very useful for my case.

2) Seems one thing we can do is to call Configuration.addAnnotatedClass for each of our own annotated entity classes e.g. by hard-coding those classes at compile time. Or ... alternatively by using Reflections or Guava we can find all (i.e. our own) entity classes from a given package dynamically at runtime, loop through them, and still call Configuration.addAnnotatedClass. The only problem with Reflections is that it comes with quite a few dependencies of its own. So we have to add 9 new JARs for this simple thing (what a pain) if we decide to use Reflections. With Guava it's somewhat easier, we can just call
ClassPath.from ( Thread.currentThread().getContextClassLoader() ). getTopLevelClasses(pckg).

If anyone has a better approach - feel free to provide it.
I will accept the best answer, not necessarily my answer.

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peter.petrov
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  • I just went through this headache myself. Starting with what seemed to be the obvious "addPackage". However, I did end up still using addPackage after adding in all the classes with the code above. It reads the package level meta data (pacakge-info.java) which I put some annotations in for custom types. – Paul Zepernick Jan 26 '18 at 16:41