Weblog for the AMIS Technology corner
Oracle
Using the MetaData Services (MDS) in a SOA environment – part 1
Feb 10th
Before I talk about the advantages en methods of using the MDS, I want to introduce myself, because this is my first public post on the AMIS technology blog. My name is Robert van Mölken and I’m 26 years old. I’m now actively working, as a SOA Consultant / Developer, for nearly 5 years. My main toolstack is SOA Suite (3,5 years 10gR3 and 1,5 years 11gR1), but also have experience with opensource BPEL / ESB alternatives from Apache.
In many big SOA application all the composites use the same canonical1 data model (message definitions) for their service contracts. Many entities and elements (complex- and simple types) are reused. Therefor it is not a good choice to use a local copy for the service contracts (WSDLs) and message definition files (XSDs) in each SOA composite project.
If you do so and a mayor (common) part of the message definitions changes then you need to update all the SOA composite projects, where these files are used, with the new version of the files. Oracle created the MDS to solve this issue. MDS stands for MetaData Services. The MDS holds all kind of xml-based files, like WSDLs, XSDs, Domain Values Maps but can also hold fault policies and event definitions (for Event Delivery Network).
ADF 11g : Fancy Master Detail or how to Highlight Related Detail Records
Feb 6th
Last week I a had a rather interesting question: Is it possible to highlight related data that is in different af:table components ? Sure you can, so I decided to write a simple example application, and share the knowledge in this post Read the rest of this entry »
Sending an email with attachment from Oracle BPEL
Feb 5th
In my previous post I described how to create a PDF file/report in Oracle BPEL (Create a JasperReport from Oracle BPEL).
Now I will describe how to sent this PDF file as attachment in an email.
Create a JasperReport from Oracle BPEL
Feb 5th
In my previous post I described how to create a Report (CDBooklet) with JasperReport in Java.
Follow this link to take a look at the post ‘Using Java to create a report with the JasperReport java API’
For this new post I created a webservice wrapper around this reporting functionality and deployed it to a Weblogic application server.
Here I will describe how to create a CDBooklet report with the Oracle SOA Suite 11g.
First we have to determine the in- and output payload for the service. You can find a detailed description of this service in my previous post.
Read the rest of this entry »
Intercepting user customization – such as column reordering in tables – in ADF 11g change persistence
Feb 4th
The requirement I was facing was simple: act on column reordering through user drag and drop in a rich table. More specifically: invoke a method in a managed bean whenever the user changes the position (or side or visibility) of a column.
At first it seemed trivial – just use an AttributeChangeListener. When that turned out not to work – this listener does not get triggered for column reordering – the challenge turned almost unsurmountable. Finally I ran into the ADF Change Persistence framework and more specifically into the concept of a ChangeManager. See for some background this article that I wrote a long time ago: http://technology.amis.nl/blog/4595/adf-11g-persisted-run-time-user-ui-personalization-or-impatient-mans-mds. Some background can also be found here: http://docs.oracle.com/cd/E15523_01/web.1111/b31974/ad_persist.htm (Fusion Middleware Fusion Developer’s Guide for Oracle Application Development Framework 11g – 35 Allowing User Customizations at Runtime).
In short: enable user customizations and configure a custom class that extends from ChangeManager to intercept the customizations.
Masterclass Oracle 11g voor Database Ontwikkelaars – haal meer uit SQL en PL/SQL in 11g
Jan 23rd
Aanstaande vrijdag 27 januari verzorgt Oracle ACE Director Alex Nuijten bij AMIS Services in Nieuwegein een Masterclass voor Oracle Database Developers: iedereen die met enige regelmaat SQL en/of PL/SQL toepast in zijn of haar werk. In deze Masterclass leidt Alex de deelnemers rond in Oracle Database 11g Release 1 en 2 met als voornaamste doelstelling de bezoekers in staat te stellen nuttig gebruik te gaan maken van de nieuwe mogelijkheden in deze 11g releases ten einde code simpeler, beter, sneller en functioneel rijker te maken.
Alex staat wereldwijd bekend als enthousiaste verteller en duidelijke explicateur (hij heeft met die eigenschappen al meerdere speaker-awards gewonnen op internationale conferenties). Hij combineert een duidelijk overzicht van de theoretische achtergrond met sprekende demonstraties en praktijkvoorbeelden. Deelnemers kunnen idealiter zijn some wat droge gevoel voor humor waarderen – en zijn in staat om in een tamelijk intensieve dag veel nieuwe kennis te verwerken.
Voor deze Masterclass is nog een beperkt aantal plaatsen beschikbaar. Zie http://www.amis.nl/amis-masterclasses/masterclass-oracle-11g-voor-database-developers voor meer informatie en inschrijving.
Create simple Java application to post JSON message to CometD Bayeux Channel using Apache HttpClient and Maven style NetBeans project
Jan 20th
The objective discussed in this article is to post messages to a CometD Bayeux Channel with a standalone Java Class – without dependencies on CometD. For example to control from Java the Slideshow introduced in the synchronized Slideshow demo application created using CometD (see previous articles Push based synchronized Slideshow demo application implemented using CometD and jQuery running on Tomcat and Publishing to CometD Bayeux Channel from inside the Oracle Database – PL/SQL based push to CometD Web Client ).
This article describes the creation of a simple Java Class leveraging Apache HttpClient to post HTTP requests (JSON messages) to a CometD Bayeux Channel. The main point is to show working code with the lest dependencies, not an optimal program (it is far from optimal). The article demonstrates how NetBeans and Maven conspire here to make the task as simple as possible. The Maven support in NetBeans allows me to simply create a new Maven style project of (arche)type Java Application.
Publishing to CometD Bayeux Channel from inside the Oracle Database – PL/SQL based push to CometD Web Client
Jan 19th
In recent articles, I have introduced CometD as framework for Server to Client and Client to Client Push: Running CometD 2 examples – locally on Tomcat using Maven and NetBeans http://technology.amis.nl/blog/14709/running-cometd-2-examples-locally-on-tomcat-using-maven-and-netbeans, CometD 2 Java Client Sample – open project in NetBeans based on Maven pom file, modify sources and run Java Based Comet Client (http://technology.amis.nl/blog/14720/cometd-2-java-client-sample-open-project-in-netbeans-based-on-maven-pom-file-modify-sources-and-run-java-based-comet-client) and Push based synchronized Slideshow demo application implemented using CometD and jQuery running on Tomcat (http://technology.amis.nl/blog/14870/push-based-synchronized-slideshow-demo-application-implemented-using-cometd-and-jquery-running-on-tomcat).
CometD allows web clients (or stand alone Java clients) to subscribe to Bayeux channels maintained by the CometD Server (Servlet). These clients can publish messages to the channels and CometD will deliver the messages to all or to selected clients – in a push-fashion. This makes it possible to push messages from the Java server side of a web application to web clients and indirectly to do the same between web clients. One example I have described of applying this technology is the synchronized slideshow: a web page is opened in two or more browsers. When a slide is selected in one of the browsers, the slide is selected in all browsers (because they all subscribed to the channel that a slide selection event was published to).
This article adds another push channel to the overall picture: it describes how the Oracle Database can publish directly to the Bayeux Channels (by posting to the CometD servlet over HTTP) and thereby perform push to the subscribed web clients. Database to browser push – how does that sound?
