Data Conflict Solution for ADF BC REST with Versioning

I would like to share sample solution for data conflict processing in ADF BC REST using versioning. When multiple users are editing concurrently the same data row - it is important to inform user before overriding changes already committed by another user. There are other approaches to implement data conflict control, you should evaluate if solution explained below is suitable for your use case, before applying it.

Sample code can be obtained from GitHub repository.

(more...)

ADF Postback Payload Size Optimization

Recently I came across property called oracle.adf.view.rich.POSTBACK_PAYLOAD_TYPE. This property helps to optimize postback payload size. It is described in ADF Faces configuration section - A.2.3.16 Postback Payload Size Optimization. ADF partial request is executing HTTP post with values from all fields included. When postback property is set to dirty, it will include into HTTP post only changed values. As result - server will get only changed attributes, (more...)

The Struggles of Personalization in ADF

A Mike Heeren & Richard Olrichs co-production

ADF comes with the out-of-the-box features of personalization. This means that whenever you configure personalisation, users can persist changes they make to the application across sessions and personalize their experience with the application. We have seen that this feature can also confuse some of our users, so it is not always wise to use this. It depends on the use case you have. However, when recently implementing personalization (more...)

The Struggles of Personalization in ADF

Uncategorized
| Jul 10, 2018
A Mike Heeren & Richard Olrichs co-production

ADF comes with the out-of-the-box features of personalization. This means that whenever you configure personalisation, users can persist changes they make to the application across sessions and personalize their experience with the application. We have seen that this feature can also confuse some of our users, so it is not always wise to use this. It depends on the use case you have. However, when recently implementing personalization (more...)

Configure and test your ADF REST Resource

In my previous post I showed the steps you have to take to create your first ADF REST resource. You can find it here: First steps with REST services on ADF Business Components. I will continue my exploration in the world of ADF REST.

We are now going to configure the URL and test the new service.

After you run your application, you will see the endpoint in your JDeveloper log:

image

The first thing you (more...)

ADF on Docker – Java Memory Limit Tuning for JVM

It might look like a challenge to run Java in Docker environment, by default Java is not aware of Docker memory limits. Check this article for example - Java inside docker: What you must know to not FAIL.  I was able to run WebLogic and ADF (Essential WebLogic Tuning to Run on Docker and Avoid OOM) on Docker previously without Java memory issues, using JAVA_OPTIONS=-XX:+UnlockCommercialFeatures -XX:+ResourceManagement -XX:+UseG1GC. However after Docker upgrade (more...)

ADF Declarative Component Example

ADF Declarative Component support is popular ADF framework feature, but in this post I would like to explain it from slightly different angle. I will show how to pass ADF binding and Java bean objects into component through properties, in these cases when component must show data from ADF bindings, such approach could offer robustness and simplify component development.

This is component implemented in the sample app - choice list renders data from ADF LOV (more...)

Find In Cache By Key ADF BC API Method Usage

What if you need to verify - if row with given key exists in fetched rowset? This could be useful while implementing validation logic. ADF BC API method findByKey - will trigger SQL call and fetch row from DB, if row with given key doesn't exist in fetched rowset. Luckily there is ADF BC API method called findInCacheByKey, this method only checks for row in fetched rowset, without going to DB - very convenient (more...)

Microservices with Oracle ADF Remote Regions

ADF remote regions - functionality available in the latest ADF 12c versions. ADF remote region runs on different server and content is delivered to consuming module through ADF remote region servlet. This allows to decouple large enterprise system into separate modules, each running independently on separate servers. Gained advantage - system becomes more scalable and reliable, even if several modules will be down, system will continue to be functional.

Concept of ADF remote regions, reminds (more...)

Avoid Blind SQL Call from ADF Task Flow Method

Keep an eye open on ADF Task Flow Method Call activities where methods from ADF Bindings are called. JDEV 12c sets deferred refresh for ADF binding iterators related to TF Method Call activities and this causing blind SQL to be executed. Blind SQL - query without bind variables.

Let me explain the use case, so that it will be more clear what I'm talking about.

Common example - TF initialization method call where data is (more...)

#DOAG2017 wrap up

doag_wegweiser

Another DOAG is over and here are my summary.

Day 1

As my presentation is planned for noon I arrived this year on the evening before, so I could attend the early sessions on 8:30.

Sten Vesterli: APEX, ADF, or ABCS? A real-life application built in 3 tools

He compares the development of a real application in APEX, ADF and ABCS. He don’t believe that ABCS is usable from end users and shows interesting (more...)

ADF Performance on Docker – Lighting Fast

ADF performance depends on server processing power. Sometimes ADF is blamed for poor performance, but in most of the cases real issue is related to poor server hardware, bad programming style or slow response from DB. Goal of this post is to show how fast ADF request could execute and give away couple of suggestions how to minimize ADF request time. This would apply to ADF application running on any environment, not only Docker. I'm (more...)

ADF Performance Story – This Time Developer Was Wrong

ADF is fast. If ADF application is slow, most likely this is related to development mistakes. I would like to tell you one story, based on my ADF tuning experience. Problem description: ADF application runs fast in DEV, when DB size is small. Same application runs slow in TEST/PROD, when DB size is large. Question - what is slow. Answer - slow means forms are loading slow. Ok, lets go to the story.

Developer decides (more...)

#DEVCAMP17 wrap up

 

Yesterday I attend the annual barcamp DEVCAMP of the DOAG development community. There are mostly developers with SQL, PL/SQL, Forms & Reports, ADF, JET background and some Java, Javascript and APEX developers too. And not to forget: 1 dba and some managers. Here are my summary.

I arrived on evening before just in time for the life cooking event and later at the bar to meet lot of the people I already know and some new too.

The morning begins with (more...)

#DOAG2016 wrap up

doag_wegweiser

Another DOAG is over and here are my summary.

Day 1

Unfortunately the early train from duesseldorf arrives not before 9:30, so I missed the first morning slot. But on the other hand I this was the slot where I had to decide between 8 presentations, which I’m interested in.

The first soft skill presentation was about creative techniques beyond brain storming. The mentioned 3 techniques was all unknown for me, maybe I give it (more...)

Mastering Oracle ADF Bindings: Advanced Techniques

My Oracle OpenWorld presentation “Mastering Oracle ADF Bindings: Advanced Techniques” is now available for download from the OpenWorld web site. In this presentation, I talk about

  • Reading the Bindings tab
  • Bindings in the ADF lifecycle
  • Working programmatically with bindings
  • Getting the binding from a component
  • Working with dynamic bindings
  • Creating a binding programmatically

If you are interested in creating bindings programmatically, you should read Eugene Fedorenko’s blog post on this. He also makes (more...)

UKOUG Tech 14 in Liverpool

I’ll be going to the UKOUG Tech 14 conference in Liverpool in December to give one of my favorite presentations: “APEX or ADF? From Requirements to Tool Choice”. I’m also leading the Development Tools roundtable, which is always lively at the UKOUG conference. If you want to discuss your options as a developer in the Oracle world, UKOUG Tech 14 is the place to be.

APEX or ADF? From Requirements to Tool Choice
APEX or (more...)

Using Bean Validation in Oracle ADF

Oracle ADF version 12c runs on JEE6 container Weblogic 12c.  ADF Faces 12c (current version 12.1.2) is based on Java Server Faces 2.1 standard. Version 2 of JSF introduced support for Bean Validation , as described in  JSF specification ( Chapter 2.5.7). To summarize: it basically states,  that java bean properties , annotated with Bean Validation constraints, are going to be validated

ADF Book Bundle – get one free!

Packt Publishing has a “buy one, get two” offer that runs until Wednesday. If you don’t have my ADF books, this would be a great opportunity to buy my new book Oracle ADF Enterprise Application Development – Made Simple: Second Edition and get a free copy of Developing Web Applications with Oracle ADF Essentials (or the other way around ;-)

The Long Tail of Application Usage

A long tail is a distribution of some data point where a few data point have a high value, but most of the data points have a much lower value. When sorting the data points by value, there will be a large “head” and a long “tail”.

Application usage displays the “long tail” characteristic: A few screens are used much more than others.

Long tail of app usage

If you are re-developing your application, for example moving from Oracle Forms (more...)