Replace EntityService with new DocumentService

[rsoika]

As a result of issue #191, we come to the conclusion, that we can not optimize much on the database side by changing the OneToMany relationships or fetch types. Performance slows down in case of a lot of equal key-value pairs in the table textItem (e.g. more than 10.000 entries of same $modelVersion).
But after all we see that Lucene is still able to solve such complex queries very fast.

New approach for version 4.0.0:

We will follow now a complete new approach for version 4.0.0:

• Lucene becomes an integral part of the imixs-workflow engine (EntityService).
• We will drop all oneToMany relationships from the Entity JPA Bean.
• The EntityService will be replaced with a new DocumentService
• The DocumentService will index each entity during the save method (lucene)
• We can skip the lucene -adapter project and also the lucen plugin
• We provide new Finder Methods in the DocumentService using the Lucene Query Builder
  *We provide a migration service bean which implodes old Entity jpa objects and migrate them into Document jpa objects and adds them into the lucene index.

Finally we need to refactor all JPQL statements used until now.
Also we need an admin interface to re-index entities on some simple criterias (e.g. type, $modified, $created)

[rsoika]

Migration Notes 4.0.0

This are comments concerning the migration from Imixs-Workflow version 3.x.x to version 4.x.x.

Packages

The following java packages are deprecated in version 4.0.0 but still available to support the migration:

• org.imxis.workflow.jee.ejb
• org.imxis.workflow.jee.jpa
• org.imxis.workflow.jee.util
• org.imxis.workflow.plugins.jee

The following new packages are introduced with version 4.0.0 :

• org.imixs.workflow.jpa - contains the persistence JPA classes
• org.imixs.workflow.ejb - contains the services EJB classes
• org.imixs.workflow.plugins - contains all plug-in classes

Persistence

With version 4.0.0 we introduced a new persistence layer. There is now only one single JPA entity bean class 'org.imixs.workflow.jpa.Document'. The Document class replaces the deprecated Entity Class with all additional index classes.

The package 'org.imxis.workflow.jee.jpa' is still available in version 4.0.x to support the migration path. We will drop this package with version 4.1.x finally.

EJBs

All Imxis Service EJBs are moved into the package 'org.imixs.workflow.ejb'. The EntityService EJB was replaced with the new DocumentService EJB.