Persistence

Persistence in Sakai - @Former user (Deleted)

• What is persistence?

  • Taking temporary data (like in-memory program data) and storing it in a more permanent form

  • Putting program data somewhere so you can retrieve it later (e.g. after a restart)

  • Writing the information in your Java objects somewhere so you can get to it again after they are destroyed

• How do we persist data in Sakai?

  • Pretty much always use the database

    • File / binary stream storage available (using content hosting service), example: resources/dropbox tool

• Databases and Sakai

  • Settings are in the sakai.properties file

  • 3 accepted ways to persist data to the database

    • JDBC - advantages and disadvantages? same as Spring JDBC but harder to use!

    • Spring JDBC - advantages and disadvantages? not ORM, more work, more control

    • Hibernate - advantages and disadvantages? ORM, easier, less control

• JDBC in Sakai

• Hibernate in Sakai

• Example - Enhance Task List Tool to persist tasks

  • Tasklist Project XML Hibernate dependency

  • Tasklist Hibernate 3 HBM file

  • Tasklist Task object

  • Implementing the Manager API by extending HibernateDaoSupport

  • Spring injection of the SessionFactory

  • Build and Test