Thursday, June 28, 2007

Frequently asked questions, or "the human Google"

I really like the JDeveloper Forum on OTN. I have a little desktop widget that uses RSS to show the latest posts as they come in. I read the forum almost like a Blog - it's always interesting, informative, and helpful to see what issues people are grappling with; lots of times, I get new ideas to try by reading posts there. I also try to answer as many of the questions that come up as I can. Why? The forum was helpful to me starting out, and, personally, I'd like to see others be successful with JDeveloper and the marketplace for JDeveloper to grow - purely for selfish reasons. I'm a consultant, and the more potential customers use JDeveloper and Oracle stuff, the more potential customers for me and the company I work for.

As I read the posts, there are some that just come up over and over and over and over. Lots of times, I'll answer the questions by doing a quick search on the forum and posting the link (hence "the human Google"). So I thought I'd compile a list of questions and answers here, sort of an unofficial FAQ. For what it's worth, I mostly use ADF Business Components and ADF Faces - not much of an EJB/Swing guy at the moment, so don't expect to see Swing/EJB questions.

By the way, if there's a better answer somewhere or something that should be added, let me know and I'll update the list - just post a comment to this entry.

Some of the questions/answers are a bit tongue-in-cheek ;)



Question: I'd like to create a page to frobdigate the whigginator. It's urgent so please help me!

Answer: Would you now? Honestly, there are a fair number of questions on the forum that are about this comprehensible. If you want a good answer, be sure to provide enough information so that the readers at least know what you're talking about.



Question: When will version xyz of JDeveloper be available?

Answer: When it's ready. I've been guilty of asking this question a few times myself.



Question: How do I convert among java.util.Date and oracle.jbo.domain.Date and java.sql.Date

Answer: Here's a good post that gives a few examples.



Question: How can I create two drop-down list boxes (af:selectOneChoice) such that when I pick a value from the first one, it changes the values in the second one - for example, when I pick the State from the first, the second one should contain a list of cities in that state?

Answer: Frank Nimphius of Oracle has written about this.



Question: I want to add security to my Faces application where I can validate the username and password against a database table. How do I do that?

Answer: Here's one way.



Question: blah blah blah OAF blah blah Oracle Applications Framework blah blah OA Framework?

Answer: Try the OA Framework forum on OTN.




Question: I want to have a gap-less sequence number as the key for my table, how

Answer: No, you don't.




Question: but I wasn't finished with my question yet.

Answer: Yes you were.



Question: OK, I understand I should use a database sequence. Why is the number negative/how do I use the sequence?

Answer: Have a read of the ADF Developer's Guide for Forms/4GL Developers, section 6.6.3.8 for starters. Then, read the rest of that document ;)



Question: How can I display images that are stored in a blob in the database?

Answer: Read this post



Question: How can I use a drop-down list (af:selectOneChoice) inside of an editable table (af:table)?

Answer: Steve Muench of Oracle did a nice screencast showing how to do that.



Question: How can I call a stored procedure from my application module code? I don't want to open a new database connection

Answer: Check out this post.



Question: I am trying to connect to my Oracle XE database and am getting errors. What do I need to do?

Answer: The Oracle XE connection information is localhost:1521:XE. Most likely, you forgot to change the SID from "ORCL" to "XE" when you set up the connection.



Question: How do I get the selected label of an af:selectOneChoice? Every time I try, I just get a number

Answer: Frank Nimphius to the rescue again.



Question: How do I highlight the selected row in an af:table?

Answer: Check out this post for a couple of answers.

5 comments:

Ric said...

John,

Your post is spot on and very amusing to say the lease.

--RiC

shay said...

I hear you on the "why don't they search before they ask".
How I wish I could post this instead of an answer:
http://justfuckinggoogleit.com/

Tif said...

Hi all,

May be i'm wrong but i can't find an "official" Jdeveloper FAQ. Also i'm trying to build my own one. I will very enjoy if you can have a look on it and giving me some advices => http://my.opera.com/Tiftif/blog/faq-jdeveloper-english
Feel free to use these first ideas to build an "official" FAQ which is still missing and could make the forum lighten.

Best regards,
Tif

Anonymous said...

It would be great if all these FAQs are available in a single place. Oracle has recently introduced http://wiki.oracle.com. Perhaps, http://wiki.oracle.com/page/ADF+%26+JDeveloper is the best place for FAQ ?

Sildenafil Citrate said...

I have just the frequently asked questions and many of those questions I had in mind, thanks for making this post, it cleared everything up!