Blog Xebia France

Paris JUG: Party Data Grid on May 12th

Next party of Paris JUG will take place on Tuesday, May 12th, 2009 in the places of ISEP.

This party is divided into two parts:

• Grid, lasted 1 h 30, introduced Jean-Michel Bea (Fastconnect) dated, Cyrille Le clerk (Xebia) and Erwan Alliaume (Xebia)
• JavaRebel, lasted 30 minutes, introduced by Jevgeni Kabanov, founder of ZeroTurnaround

Paris JUG is victim of its success: number of places is limited and inscription is now compulsory, did you reserve your?

Here is the detailed programme of the party:

Read the continuation of this article

Maximum Maven

Maven, the famous tool of management of build of plan, is often considered as difficult of approach. The main unpleasant, often highlit point, is the complexity of management of the famous files pom.xml, which describe the processes of build. To motivate itself, it is important to remember that, among those who took the time to be interested in it, very rare those are who turn around. As in code, there are good practices which, if they are respected, allow to meet there easily.

The road is long but the way is free. Let us see therefore together some rules of good behaviour to keep pom maintenables and to prolong the honeymoon with Maven.

• Use an artefact repository
• Declare all your direct dependency
• Use properties everywhere where it is possible
• Use profiles
• Think, please, about the cutting up of your artefacts
• Avoid leaning on local preferences
• Dare to write plugins

Read the continuation of this article

What you perhaps missed in the first quarter 2009

Here is the list of tickets most read on this blog in January, February and March:

Why agile plans cannot be led for a fixed sum

In subcontract of software development, the most frequent contractual practice that is said about plan for a fixed sum. The notion of fixed rate has no report, in principle, with the process of development or the practices of engineering used in the realisation of plan. It is simply a question, in the spirit of the contracting parties, of fixing the precise outlines of their trade relations, and of defining their mutual obligations in term of costs, of delays, of method of payment and of delivery. In a State of right, and as far as they are not excessive, these contractual dispositions have the force of law, and protect efficiently the absorbing parts.
To look really there however at the neutrality of the fixed rate in relation to the process of development is less obvious. Conceived historically to meet requirements of bet in competition of the suppliers of American Department of the Defence, contract for a fixed sum is born in the same substrate as the process of development in waterfall initially described in 1970 by Winston W. Royce in Managing the developpement of broad software package systems.
This process of development is strongly reappraised, under the empirical official report of its relating failure, and at the instigation of agile methods today. I think as for me that the "waterfall" will be perceptible over the years as the youthful blindness of a still youthful industry, in search of its identity.
The question which interests us here is to know if the plan for a fixed sum will survive the waterfall. In other words if it is possible to lead for a fixed sum a subcontracted agile plan. Some people think of it, and some integral filters offer such contracts incidentally. I intend as for me to show here that agility and fixed rate are based on radically antinomic financial logic, which makes them hardly compatible.

Read this article

GWT GALAXY

You perhaps attended in Paris JUG on GWT and you willy-nilly told yourself by going out of the conference which it was absolutely necessary to put to you in GWT. On top of that, the step to be crossed is not huge: it is of the Popular dance (this should go), livened up with many bookshops as in the world J2EE, graphic booksellers who throw it are available That of advantages! But by where to begin?
We are therefore going to make a general survey not exhaustive, but sweeping a lot of what is used in the galaxy GWT: plugins, general and graphic frameworks and IPA - INTERNATIONAL PHONETIC ALPHABETS.

Read this article

Quartz and Spring Scheduling

Quartz for those who still do not know it, is an ordonnanceur. He allows to plan tasks for repeated or punctual executions. Possible plannings go of simple infinite repetition, in the calendar repetition using the syntax of cron (every day at midnight, on January 31st, 2009 at 12 h 00). Quartz is envisaged for all kinds of applications going of programmes basic standalone to the big systems distributed JEE.
For his/her part, scheduling Spring gives the choice us between Timers Java and Quartz. With his interfaces, Spring allows us to plan Jobs, very easily, directly in ApplicationContext. On the other hand, the management of dynamic plannings is less obvious. In this article, I will introduce you the IPA - INTERNATIONAL PHONETIC ALPHABET Quartz in main lines, then the planning Quartz with Spring Scheduling will be set up.

Read this article

Exceptional Paris JUG on February 10th, 2009, one year already!

It has already been one year ago. Paris JUG unites now about 150 persons every month and seems to have made the emulators with about ten Popular dance User Groups in France.

Antonio Goncalves, David Dewalle and Zouheir Cadi organise, to celebrate this birthday, an exceptional party on Tuesday, February 10th, 2009 in the places of Fiap.

In :

• 19 h 45 - 20 00: Reception.

• 20 h 00 - 21 00: 1st session quickies:
  • Paris JUG, on 1 year already by Antonio Goncalves, David Dewalle and Zouheir Cadi.
  • JUGS in France with The team of Paris JUG, Christophe Jollivet (Tours JUG), Xavier Hanin (Claret JUG), Nicolas Leroux and Stephane Epardaud (Riviera JUG), Nicolas de Loof (BreizhJug), Sebastien Roul (Nantes JUG), Christophe Meyer, JM DOUDOUX and Xavier Roy (Lorraine JUG), Ga l Blondelle (Toulouse JUG).
  • Presentation of Framework Wicket by Tarik Filali Ansary.
  • JAZOON 09 presentation of conference and of news last by Christian Frei.

• 21 h at 21 h 45: Sideboard.

• 21 h 45 - 22 45: 2nd session quickies:
  • Parleys by Stephan Janssen.
  • Presentation of Popular dance 7 Dolphin by Thomas Chamas.
  • How to create a video game there 3D in Popular dance with OpenGL? by Julien Gouesse.

• 23 h in: 3rd half of juggers, this time it is preferable (or even essentials) to participate in it to register.

Let us come many and thank you still to Antonio, David, , in , to the sponsors and to the partners!

Inscriptions are opened: to attend in party and for 3rd half (Chestnuts and Blackcurrant 34, street Gassendi 75014 Paris next to the street Daguerre).

DDD The conception which links functional and code

DDD, Domain Driven Design, leaves an impression that often brings to one of the following comments:

• I have already heard it spoken (but I do not know what that is)
• I believe I have seen him in TDD
• It is as MDA? this walks with group of acronyms MDSD, MDD
• Sorry? To you ace a problem with your key " D" 

The objective of this article is to introduce you DDD, its stakes and its interest.

In DDD, there is Driven Design, it is therefore a technology of conception. You should not merge with the techniques of development (Driven Development) as for example TDD (Test Driven Development).

DDD is neither a method nor a technology. DDD is a way to think of conception around code, to collaborate and to communicate with the functional experts.

This element of communication is an important dimension. That is why we will approach topics in this article according to:

• What conception, which is the present state
• Brings what DDD in the more classical techniques of conception
• Brings what DDD in the communication of teams

Read the continuation of this article

Complete Flux RSS by default

A little less than a month ago, we had asked you through an opinion poll if you preferred having a complete flux RSS, which contains the entirety of every article, or a flux RSS cut down, in who only one an extract of every article is visible.

You were numerous to participate in opinion poll, we thank you for it! Results are the following:

Thank you also for your comments. In the light of these last, we put in disposition two fluxes RSS: a complete flux, and a flux  "summed up " .

We overbalanced the flux by default towards the complete flux, since two thirds of you prefer this version.
If you prefer the ancient version summary, it will be necessary you to change the address of the flux in your READER RSS, the address of the new flux summed up is: http://feeds.feedburner.com/XebiaFranceSummary.

For information, we used the plugin DualFeeds for WordPress, since by default WordPress does not give the possibility of displaying both fluxes. DualFeeds was not since updated a bit, but it works perfectly well with WordPress 2.7!

Sponsor of conference XP Day France Xebia 2009

Xebia sponsors which will be held on May 25th and 26th, 2009.

You are in search of new ideas to make more efficient your software plans of development ?

You wish their borders in knowledge more on agile methods, their benefits, 
You set agile practices up within your plans and you want to confront your returns of experience with those of other practitioners 

Appointment on May 25th and 26th, 2009 for .

Read the continuation of this article

What you perhaps missed in the fourth quarter 2008

Here is the list of tickets most read on this blog in October, November and December:

RIA CONTEST: FLEX / Silverlight / GWT / Echo3 / JAVAFX

After the Xebia Web Framework Contest of last year, the topic of XKE of October was a contest new devoted in RIA.

The purpose of this day was to develop an application of management of playlist of music pieces. In promoters of Agile methods, specifications were given in form of Product Backlog. Three sprints of a length of 90 minutes allowed all to follow the evolution of different achievements. A web SOAP service gave different data: Artist, Album, Titles and Cases of album.

Five teams were constituted, five frameworks were therefore chosen:

• FLEX 3
• Beta 2 Silverlight 2.0
• GOOGLE GWT 1.5
• Echo3
• JAVAFX PREVIEW SDK

At the end of this day, every team could express a significant return of experience.

Read this article

Diagnosis of remote JVM

To develop a Popular dance application, it is well. To make her competitive, it is better.

However, who says "performance" , says "measure" . Indeed, it is necessary to be able:

• know the parametres of launching of JVM,
• measure footprint memory and the behaviour of Garbage Collector,

This article is going to describe in a first part the different tools allowing to collect this information in place. The second part concentrates on means to get this same remote information.

Read this article

Analyse memory of JVM

Tuesday, 10 am
- Production  Hello, plan, since 10 minutes they see crossing ' OutOfMemoryError ' messages. What does be made?  
- Plan  Augment the memory of JVM, double it value of option-Xmx  

Tuesday, 1 pm
- Production  Hello, plan, since 5 minutes they again see crossing ' OutOfMemoryError ' messages. What does be made?  
- Plan  Augment the memory of JVM, still double the value of option-Xmx  

Tuesday 18 hours
- Production  Hello, plan, since 2 minutes they see crossing still ' OutOfMemoryError ' messages. What does be made?  
- Plan  Hushed up, up, up.. 
- Production  More team plan, the night is going to be long  

This small stage is a classic, an air of d j vu but what to make? If your application has already suffered a battery of technical tests, to augment memory is seldom good solution. The stage described above lets think of be traditionally called an Escape Memo (Memory Leak). In reality, with recent JVM, escape memo does not exist, I prefer speaking about accumulation of unwanted objects. This article is going to show you how brings this accumulation to light with tools jmap, jhat and Eclipse Memory Analyser.

Read this article

B tisier on 2008

The epoch takes part in it: to end the year in beauty, and to exploit an expression which makes TF1's fatty cabbages, here is a selection of pearls which we met in 2008, on plans or on the cloth.

She comes to supplement our selection of last year.

• Freedom
• Worries with your applications, they are middlewares.
• Exceptions are friend
• Art to reinvent the wheel
• They are never too much sure

Do not hesitate to post in comment your own meetings of the third A type to you to play!

Read the continuation of this article

For or against the flux RSS cut down?

We have had again and again inside these last months a debate concerning the form under which we display our articles in the flux RSS of the blog. Up to now we displayed you a flux cut down, that is articles cut in the flux RSS, and it is necessary you to open the article on the blog to show it completely.

Rather than to discuss still during several months, we told ourselves that the simplest was indeed to ask you for your opinion, faithful subscribers in the flux RSS.