hibernate-ips

This project is an attempt to provide Hibernate support to Glassfish 3.1.1 using the Glassfish Update Center.

Status

This project is currently experimental.

Installation

To install Hibernate support for Glassfish:

1. Start a pkg.depotd server like this:

    pkg.depotd -d ~/pkg-working-directory -p 10000 --rebuild
   

   It may be possible in the future to avoid having to run such a server; see this link for details.

2. From the root of this project, run the following:

    mvn clean install -Drepourl=http://localhost:10000
   

3. With the pkg.depotd server still running, start Glassfish's updatecenter tool:

    $GLASSFISH_HOME/updatetool/bin/updatetool
   

4. In the update tool, press the Edit Properties... button.

5. In the resulting dialog box, press the Add... button.

6. Choose a name for the publisher. This name looks like it must follow the rules of a valid hostname.

7. For "Repository URL", supply http://localhost:10000.

8. Press the OK button.

9. Press the OK button.

10. Choose the Available Add-Ons tree node.

11. From here you should be able to find a package named hibernate-ips. Install this package like you would any other Update Center package.

12. Once you've gotten here, you may terminate the pkg.depotd server. That's it!

What Really Happens

This project simply arranges for the Glassfish Update Center to do all the heavy lifting. The heavy lifting, though, isn't that heavy.

A hibernate-ips-<version>.jar file is deposited in the $GLASSFISH_HOME/glassfish/lib directory, the directory whose .jar file contents form part of the Glassfish common classloader. This .jar file is empty, but contains a MANIFEST.MF file with a Class-Path: header. The elements in the Class-Path: header all refer to other .jar files within the $GLASSFISH_HOME/glassfish/ips/hibernate-ips-<version>-dependencies directory, which is also created by this project, and which is full of Hibernate's dependencies. The net effect is that the hibernate-ips-<version>.jar file serves as a kind of façade to the contents of the related dependency directory.

A Note On Dependencies

Hibernate's pom.xml declares lots of dependencies. hibernate-entitymanager does too. Some of these dependencies are--in practice--mutually exclusive. For example, you'll usually have one cache provider, not several at once.

This project is set up to dump as many of Hibernate's transitive dependencies as possible in $GLASSFISH_HOME/ips/hibernate-ips-<version>-dependencies. All of these dependencies will be on the Glassfish common classpath, visible to all applications.

The one dependency (and its transitive dependencies) that is excluded is SwarmCache, because it requires a version of JGroups that is older than the version of JGroups that is required by several other dependencies. SwarmCache is an older, less popular cache provider and hence seemed like a dependency that should not be included by default.

The old version of Hibernate support for Glassfish used to package up the no-longer-produced hibernate3.jar file, which was a kitchen sink type of .jar file that packaged Hibernate along with several unspecified dependencies into a single file. Hibernate versions after 3.5 no longer produce this .jar file, requiring that the individual developer declare dependencies on what he needs (which cache provider to use, etc.).

Providing this kind of support for an application server, however, means that by definition we don't know what dependencies the developer is going to want. So we include all of them that we can.

Further Questions

Alexis Moussine-Pouchkine's crash course on IPS is helpful to understand what's going on here.

All other questions should be directed to the author, Laird Nelson, at ljnelson at big horking email provider starting with g.