Lab12 EJB JPA JSF CRUD: with explanation

Summary

The video demonstrates how to build a Java EE employee information application using EJB, JPA, and JSF. The application supports the four CRUD operations—create, read, update, and delete—on a database table.

Main Concepts

• JPA maps the database table to a Java entity.
• EJB provides database operations through a generated facade.
• JSF supplies the web pages and form controls.
• A session-scoped managed bean connects the JSF pages to the EJB layer and handles user actions.

Method and Project Structure

1. Create the database table

   • Use NetBeans’ sample JDBC database.
   • Create a Person table with these fields:
     • id_person: integer primary key
     • name: varchar, length 50
     • email: varchar, length 50
     • phone: integer
   • Add sample rows, ensuring each ID is unique.

2. Create the enterprise application

   • In NetBeans, create an Enterprise Application project containing an EJB module and a web module.
   • The demonstration uses GlassFish and Java EE 7.

3. Generate the persistence layer

   • In the EJB module, create an entity class from the database table.
   • Create a persistence unit and use a List collection type.
   • Generate a session bean or facade for the entity. Its methods provide operations such as creating, finding, editing, and removing records.

4. Set up the web application

   • Add JavaServer Faces to the web module.
   • Create a controller package and a JSF managed bean named PersonController.
   • Set its scope to session and inject the person facade.
   • Add a method that calls the facade’s findAll operation to retrieve records for display.
   • Add a Person property with getters and setters so JSF forms can bind to it.
   • Add controller methods for inserting, deleting, and updating records.

5. Build the employee list page

   • Use the main JSF page, index.xhtml, to display a data table populated with database records.
   • Show each person’s ID, name, email, and phone number.
   • Add an Insert record link that navigates to the insert page.
   • Add Delete and Update actions for each row.
   • A border attribute can be used to add a table border.

6. Create the insert page

   • Create an insert.xhtml JSF page with a form bound to the controller’s Person property.
   • Provide fields for the new record and an Insert button.
   • The button calls the controller’s insert method, which invokes the facade’s create operation and returns to the list page.

7. Implement deletion

   • Add a delete action to each row, passing that person object to the controller.
   • The controller calls the facade’s remove operation and returns to the list page.
   • The demonstration includes a confirmation prompt with OK and Cancel options.
   • If a JSF command link behaves unreliably, try a command button and check that its markup is correctly closed and quoted.

8. Create the update page

   • Create an update.xhtml page with a form for editing a record.
   • Do not expose the ID field; the demonstration allows editing the name, email, and phone number.
   • Use an update button to submit changes and return to the list page.

9. Build and test

   • Clean and build the enterprise application before running it, particularly after making changes.
   • Run the application on the configured server and check that the list displays database records.
   • Test inserting, deleting, and updating records, then verify the changes in the database.

Practical Lessons

• Use the correct JSF page type and ensure component tags are properly closed.
• JSF-bound properties need getters and setters to be available to the page.
• Clean builds can help avoid errors caused by stale or incompletely built project files.
• The application separates database access, request handling, and presentation across the EJB module, controller, and JSF pages.

Speakers and Sources

• Speaker: One instructor or narrator throughout, attributed to Thirumurugan Shanmugam based on the channel information.
• Technologies and tools mentioned: NetBeans, the sample JDBC database, Java EE 7, GlassFish, EJB, JPA, and JSF. No additional speakers or external sources are identified in the subtitles.