In the past I used develop using Designer. Although it's already years ago I have warm memories to the tool. In Designer you could mark table-columns as descriptor-items, if I recollect correctly. I can't remember how it's done exactly and since I have noa running Designer install anymore I can't check. But I know that it was a check box on the item. So you can have multiple.

Descriptor Items are used to generate a reference on a details page to denote for which parent you are editing details.

In JHeadstart I found that you can give up only one item as a descriptor item on the group. In my latest project I had to create a maintenance application on a datamodel that had a table where the columns on their own were not descriptive enough. You could argue that I had to introduce such an attribute. For example a name or code attribute that is unique. But functionally the table did not need to have one. But the entity related to another entity for which I generated a detailgroup. And on that page a reference to the 'non-descriptive' table-row was generated. on one of it's columns. Most of the rows had the same value on the column though. So I wanted to connect all the attributes, together with a lookup attribute from another table and have that as a descriptor.

Luckily the solution I used was easy. And maybe as a JavaADF-JHeadstart expert you'd not be surprised. But for those who struggle, here's how I did it.

First I adapted the ViewObject of the parent-entity.



If needed add extra entity objects for attributes you want to relate to in your descriptor items. In an entity Object in ADF-Business Components by default the complete entity name is used for used as a table-alias. I normally I don't care, but if I want to adapt the ViewObject I find that inconvenient. So I replaced them with table three-letter-shortages.

Then under the Attribute nodes, click on the New Attribute button (bottom right):


Then you get the following screen. Give the new attribute a name, check the box "Mapped to Column or SQL". Then you can give it an alias (the name the expression gets in the resulting SQL Statement". And give in an expression. I found it handy to first build up the sql statement with the particular expression in Pl/Sql developer and copy and paste it. Then I'm pretty shure it will work.

If you've done it correcly, following your needs, then the new attribute is found in the resulting SQL Statement:


You can adapt it by giving an order by and an extra where-clause-condition. But I found it also handy to copy and paste the complete sql statement and try it in Pl/Sql Developer. That prevents me from surprises later on.

Having done that, things are straight forward. Go to the JHeadstart Application Definition Editor. And on the parent group add the descriptor-attribute as an item. Set the Java-Datatype etc. correctly but make it hidden (make sure all the 'show-on'-checkboxes are unchecked). Although it's hidden I gave it a prompt. Just to recognise it directly when I stumble on it.

Then on the group-page you can set the descriptor-item selector on the particular item.

The solution is simple. But it would be handy to have checkboxes on the items so that you could just check every item you want to have in the descriptor... (going the Designer way).

This week I finished a JHeadstart generated application. Indeed I found that using JHeadstart, espessially because of the Velocity Templating framework, you get about the same productivity of Oracle Designer.

When you generate an application using JHeadstart, it generates also a Home.jspx for you. If you use this Home.jspx as your landing page (because after logging in by default you "land" on this page) you find that it lacks a menu. And maybe you want some other elements on this page. Of course you can edit the generated Home.jspx, adding the menu-facet and the other elements. But I found that sometimes JHeadstart regenerates the Home page.
If you use Subversion (or another version control system) and had committed your Homepage then you can reset your Home page back from your repository. But certainly I forget this 3 out of 4 times.

So I thought: lets generate the home page together with the other screens.

To do that you have to create another group in the application service with the JHeadstart Application Definition Editor. Call it the Home group.
Uncheck the 'Bound to Model Data collection'. Of course you do not have to choose a Data Collection.

As a layout style choose: Form.
Set the search settings both on false.
As tab-name I would choose "Home".
For a display title you can choose: "Welcome #{jhsUser!=null ? jhsUser.displayName : facesContext.externalContext.userPrincipal.name} to the Service Oriented Scheduler Maintenance Application!". In fact I copied this from the original generated home page. Of course I gave onather application name (it used to be "JHeadstart demo application").

Under Operations uncheck every DML operation.

Since there is already a "Home" button in the Global Menu, I do not want to have the Home page in the application menu. So I unchecked "Add Menu entry for this Group" under Customization Settings.

For a Group it is mandatory to have a Descriptor Item. But I did not want any items on my page. So what I did was to create one item, called "Home" (or what ever you like).


Uncheck "Bound to Model attribute?".
As a Java Type, I choose "String" (but that does not do anything) and as a display type "Hidden". Furthermore I set the Display properties all on False, and unchecked the Search options. But since I had a hidden field, these options might do nothing. I did not check.

Now if I did not forget to mention anything, the home page is generated for you, as you like, with the proper menu. You can adapt it to your wishes by adding other elements as Items (like an image for instance).

And here is my Do It Yourself-Home-page:

In my current project I created a Java ADF 10.1.3.3 application. Actually I generated the whole bunch with JHeadstart 10.1.3.3. Pretty cool stuff actually.
At the end I had to deploy the application to a proper application server. That is: not the embedded OC4J in JDeveloper, but in my case the Oracle 10.1.3.3 application server that runs our SoaSuite.
And I couldn't find a proper document that tells me how to do that. With some searching around, and "with a little help of my friends", I found three documents:

• http://www.oracle.com/technology/obe/obe1013jdev/10131/deployment/deployment.htm
• http://www.pascalalma.net/2008/05/31/oracle-adf-medior-deployment-of-adf-applications-and-using-connection-pools/
• http://download.oracle.com/docs/html/B25947_01/bcservices002.htm#sthref625

The first one tells you how to setup your deployment descriptors. It will give you at the end an EAR file that you can use to deploy to an J2EE application server.

But by default JDeveloper ships all your connections in the connection navigator in the model-project's JAR file. And also by default it deploys with a connection-descriptor in the JAR file with the database-connection you used at development time. This is of course not usefull when you deploy the EAR file to a test, acceptance or Production environment. The second post, by Pascal Alma, solves these things.

The last link points to the adf-developers guide where is stated how to change the model-project to use a datasource instead of a fixed JDBC-url.

Below I created a step by step guide to prepare for the proper deployment. For creating the actual deployment profiles I refer to the first link above.

Disable deployment of Jdeveloper Connections.
To disable this feature:

1. Go to the jDeveloper Preferences.
   
   
2. Go to the Deployment node and disable the checkbox “Bundle Default data-sources.xml During Deployment”.

Change Application Module to use Datasources

1. Right click on the Application Module and choose Configurations
   
   
   
2. Click on the Edit button
   
   
3. Set Connection Type.
   Set connection Type on “JDBC DataSource” and name the Datasource something like jdbc/FDS.
   
   
4. Click on OK.
   

Now you can create a deployment just following the steps on: http://www.oracle.com/technology/obe/obe1013jdev/10131/deployment/deployment.htm.
Having done that, you can create an EAR file by right-clicking on the deployment profile in the deployment project. And choose EAR-File:

This will create an EAR file in the deploy folder of the project. This file can then be used to deploy to the Application Server. This is quite easily done in the Application Server Control application (http://<applicationserverhost:port>/em). I might write an separate article about that later.

After that you need to create a datasource in the application-server. How to do that is a pretty straightforward task usually done by an Application Server Administrator. But I probably write a separate article about that another time too.

I hope this helps preventing you for searching around as long as I did. If you were searching already for about a day, I'm sorry you did not find me earlier...