Author Archive

Axon Framework 0.6 released

August 8th, 2010 by Allard Buijze
(http://blog.jteam.nl/2010/08/08/axon-framework-0-6-released/)

Today, I released version 0.6 of the Axon Framework. 0.6 has many new features and is another step towards full production readiness. There is still some work to do, but first, let’s take a look at what has changed…

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Axon Framework 0.5 released

April 24th, 2010 by Allard Buijze
(http://blog.jteam.nl/2010/04/24/axon-framework-0-5-released/)

Today, I finalized the 0.5 release of the Axon Framework. There is quite a number of changes since the 0.4 version. The 0.5 version is a major step towards production readiness of the framework.

Besides some changes to existing building blocks, such as the event bus, which is now much more powerful, the 0.5 version also includes some new features.

Read on to find out more.

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Measuring code quality with Sonar

February 26th, 2010 by Allard Buijze
(http://blog.jteam.nl/2010/02/26/measuring-code-quality-with-sonar/)

sonar-blackonwhite At JTeam, we continuously strive for good quality code. The reason is very simple: bad quality code slows down the development process. The small investment pays out in even the simplest of projects.

Measuring code quality is not a matter of a single metric. Instead, software quality has many aspects, some of which can be captured in metrics. Those metrics can be nicely assembled within a single application, which gives a nice overview of the state of an application: Sonar.

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Greg Young to attend on DDDnl meetup about CQRS on March 1st.

February 24th, 2010 by Allard Buijze
(http://blog.jteam.nl/2010/02/24/greg-young-to-attend-on-dddnl-meetup-about-cqrs-on-march-1st/)

On March 1st, Erik Rozendaal will give a presentation about Command Query Responsibility Seggregation (CQRS). Greg Young, one of the masterminds behind CQRS, has confirmed that he will be present during this meetup too. Seems like a good recipe for an interesting evening.

Attendance is free, but registration is required. Read on for details.

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Axon Framework – the CQRS framework for Java – version 0.4 released

February 21st, 2010 by Allard Buijze
(http://blog.jteam.nl/2010/02/21/axon-framework-the-cqrs-framework-for-java-version-0-4-released/)

logoLast week, I published the 0.4 release of the Axon Framework. Axon helps developers build high performance, scalable and extensible applications using the CQRS pattern. The 0.4 release is a major step towards 1.0, and includes transactional event handling, high-performance caching repositories and easy configuration of event sourcing support. Furthermore, we have also built a demo application that uses Flex to get real-time updates pushed from the server.

Read on to find out more.

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CQRS – Designing domain events

January 27th, 2010 by Allard Buijze
(http://blog.jteam.nl/2010/01/27/cqrs-designing-domain-events/)

logo Command-Query Responsibility Segregation (CQRS) is slowly but steadily gaining ground as an architecture that helps developers to develop scalable, extensible and maintainable applications. Events play a major role in this architecture, and the way you design these events greatly influence the extensibility of your application.

In this post, I describe some CQRS event basics and design considerations that help keep your application extensible.

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Rethinking architecture with CQRS

December 21st, 2009 by Allard Buijze
(http://blog.jteam.nl/2009/12/21/rethinking-architecture-with-cqrs/)

question_and_answer Many applications use some form of persistent storage to store its state. However, important information about this state is lost: why is the state as it currently is. Furthermore, a single model is used to store information that is retrieved for many different purposes, often resulting in extremely complex and bog-slow SQL queries.

Command Query Responsibility Segregation (CQRS) is an architectural style that makes a clear distinction between commands that change the application state and queries that expose the application state.

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Battling complexity in large web applications

October 20th, 2009 by Allard Buijze
(http://blog.jteam.nl/2009/10/20/battling-complexity-in-large-web-applications/)

space-shuttle-endeavour-launch-2 Nowadays, companies are hardly ever satisfied with a mere web-presence. No, websites have become true applications in their own right. Instead of being a by-product, most businesses acknowledge that the web offers them a nice channel to do business. However, the demands from the business keeps growing as each company want to be better than its competitors.

The increasing demands from the business have a direct influence on the applications complexity. Each time, especially when joining external projects, I am amazed by the way complexity is dealt with in most applications. “Building software isn’t rocket science”, but sometimes we do seem to make it just as complex.

In this article, I provide some insight in different forms of complexity, and how software development teams can design their application in order to deal with the ever growing demands from the business.

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Domain Driven Design applied

July 28th, 2009 by Allard Buijze
(http://blog.jteam.nl/2009/07/28/domain-driven-design-applied/)

In a recent project for Osix, we developed an application allowing visitors of a library to use the wireless Internet connection available there. Visitors can pay for the Internet access in two ways: an online payment, for example using a credit card or by deducting the amount from their library account. All user accounts, as well as the available products, library configurations and payments are managed from a single central application, called Digital Services Manager.

In this post, I will elaborate on how Domain Driven Design has helped us build a clean and maintainable application, mainly focusing on some technical and implementation choices that we have made.

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Project: welke.nl

July 23rd, 2009 by Allard Buijze
(http://blog.jteam.nl/2009/07/23/project-welke-nl/)

The Welke Magazine has been around for a while now and is a well-established name in the home decoration area. To follow up on the success of their paper version, MediaMij –the company publishing these magazines– decided to expand their position in the market by launching an electronic version, welke.nl. The goal of this website was to give their readers a more interactive experience and allow them to find more products that could be of interest in an intuitive manner.

In this post, I will focus on some technical and organizational topics that were addressed during the project. Read the rest of this entry »