Did You Know? -- July 2000

By Hervé Deschamps, Oracle Corporation.


Foreword

A lot of the material below comes from ODTUG 2000 that was held in Ft Lauderdale. There was some very hot stuff showed. Check out Cherokee and BC4J for example.
 

General Java Stuff

Very basic concepts: think of class as an entity type in relational world, like entity type employee. Think of an object as an instance of a class, like entity Hervé is an instance of entity type employee. Simple stuff really. Just don't ask me to define polymorphism....

How to write unmaintainable Java:  Check this out.

Good book: Thinking in Java. Bruce Eckel. Available on JDeveloper CD (in extras) or from www.bruceeckel.com.

Here is a quick road map to become Java proficient. I grabbed it from a presentation at ODTUG 2000, but can't remember the author. If it's you please let me know so that I can give you credit for this.
 
Step
Ingredients
Duration
1. Learn basic grammar and syntax of Java. Any book or Java resource web site. 3 days
2. Learn more about objects and OO concepts. Book "Thinking in Java", chapters 1-8 and 12. 5 days
3. GUI design using Swing. Sun tutorial "Creating a GUI using JFC Swing". 2 days
4. Build GUI app using JDeveloper, BC4J and Swing. JDeveloper online help and tutorials and a lot of perseverance. 5 days
5. Learn more about exceptions handling, multithreading, I/O, network. Book "Thinking in Java", chapters 9-11, 14 and 15. 3 days
6. Start pilot project using Servlet, JSP and BC4J. Book "Java Servlet Programming", JDeveloper online help on BC4J, permission from your boss. 60 days
7. Evaluate pilot, study Design Patterns. Book "Design Patterns in Java", Java reusables on the Internet.

 

Java Technologies

BC4J (Business Components for Java) is very hot stuff. It lets you build reusable components like blocks in Forms. It's all in JDeveloper and is very reminiscent of Designer module APIs and table APIs.

JSP: Java Server Page works like PSP (PL/SQL Server Page): there is an engine that reads the HTML page, transforms it in Java code, compiles it and run it. the PSP engine creates a procedure in the database and runs it.

Creating Servlets in JDeveloper is as simple as File->New->Servlet, go through wizard, right click and run!
 

Cherokee

Cherokee is Forms 7, the hottest thing at ODTUG 2000. At long last!!!! Forms deployed on the web as HTML (mostly). No more presentation applet stuff. There is still a Java applet run by the browser but it only handles communication, not display. Its foot print is currently 120K and might go up to 200K.
 

Designer

Live Demo of Oracle Designer Web Assistant 6.0
Running on an Application Server in The Netherlands, this is a live demo of the Oracle Designer Web Assistant, providing an overview of all its functionality.
 

Updateable Views

You need to tell forms which columns are read only otherwise all updates will fail. (feature).

SQL*Navigator (version?) drops the instead of triggers of an updatable views when you try to modify the view's definition. (bug).

Instead of triggers are very powerful, but ...  don't expect Forms to perform any locking when a user starts updating a record on the screen of a client-server application...
 

iPortal 3.0.

This is the new name for WebDB.

iPortal delivers the single sign-on. Quite logical when this thing is going to present portals from different systems onto the same screen.

 


Hervé Deschamps is a Technical Manager with Oracle Corporation. Over the years he has developed a number of applications using Oracle Development Tools and others.  He has an extensive experience of all phases of the development life cycle. He is also known in the technical community for his article publications centered around best custom development practices and for his user group presentations. You can reach him by e-mail at hdescham@us.oracle.com. He also maintains a web site full of articles, scripts, tips and techniques at http://www.iherve.com.