Chase The Devil

KDE 4.8 finally has a dock

2012-01-27T13:38:00.001+01:00

KDE 4.8 finally has a dock: you just have to add the plasma icon tasks. Also the flexibility around ALT+TAB is welcome. With Krusader as file manager, Thunderbird and Firefox for email and web, it is becoming a real nice desktop, but it took a while since the very bad KDE 4.0 release. It is easy to install under ubuntu 11.10 through the backports and seems very stable so far. Something quite

List of companies where I have been an employee

2012-01-11T02:14:00.001+01:00

Intern: Siemens (Berlin) IBM (Boeblingen) Osram Sylvania (Beverly, MA) Employee: Cap Gemini (Paris) working for Alcatel Silicomp (Paris) working for Alcatel Nextenso C2labs / one 0 development (San Francisco, CA) working for Whenmobile, Sony Pictures, GoPix, Technorati. Credit Agricole alternative (Paris) Prima solutions (Paris) Esearchvision (Paris) Ulink (Paris) Edifixio (Paris) Horizon (Paris

Generating random numbers following a given discrete probability distribution

2012-01-09T00:14:00.002+01:00

I have never really thought very much about generating random numbers according to a precise discrete distribution, for example to simulate an unfair dice. In finance, we are generally interested in continuous distributions, where there is typically 2 ways: the inverse transform (usually computed in a numerical way), and the acceptance-rejection method (typically the ziggurat). The inverse

Quant Interview & Education

2011-12-21T17:37:00.000+01:00

Recently, I interviewed someone for a quant position. I was very surprised to find out that someone who did one of the best master in probabilities and finance in France could not solve a very basic probability problem: This is accessible to someone with very little knowledge of probabilities When I asked this problem around to co-workers (who have all at least a master in a scientific

Gnome 3 not so crap after all

2011-11-30T18:11:00.001+01:00

In a previous post, I was complaining how bad Gnome 3 was. Since I have installed a real dock: docky, it is now much more usable. I can easily switch / launch applications without an annoying full screen change. In addition I found out that it had a good desktop search (tracker). The ALT+F2 also does some sort of completion, too bad it can not use tracker here as well. So it looks like Gnome 3

Good & Popular Algorithms are Simple

2011-11-17T12:28:00.001+01:00

I recently tried to minimise a function according to some constraints. One popular method to minimise a function in several dimensions is Nelder-Mead Simplex. It is quite simple, so simple that I programmed it in Java in 1h30, including a small design and a test. It helped that the original paper from Nelder-Mead is very clear: However the main issue is that it works only for unconstrained

Gnome 3, Unity, Crap

2011-08-17T19:09:00.000+02:00

After the upgrate to Ubuntu 11.04 I was directly on Unity. Having a dock on the left side is nice, but unfortunately, it has various bugs which makes it sometimes annoying. Also the menu on top like Mac Os X is not a bad idea, but it breaks many apps (for example Picasa). Then there is the scrollbar insanity, it's almost impossible to click on to scroll, and again breaks in some apps (for example

Carmack & GPGPU programming

2011-08-14T10:20:00.000+02:00

Finally someone who shares the same opinion on the current state of GPGPU programming. John Carmack: On the other hand, we have converted all of our offline processing stuff to ray tracing. For years, the back-end MegaTexture generation for Rage was done with... we had a GPGPU cluster with NVIDIA cards and it was such a huge pain to keep. It was an amazing pain where one system would be having

exp(y*log(x)) Much Faster than Math.pow(x,y)

2011-04-08T23:03:00.000+02:00

Today I found out that replacing Math.pow(x,y) by Math.exp(y*Math.log(x)) made me gain 50% performance in my program. Of course, both x and y are double in my case. I find this quite surprising, I expected better from Math.pow.

Best Headphones Ever?

2011-04-06T13:08:00.000+02:00

I just miraculously received some AKG Q701 headphones. I never tried really high end headphones before those. I was used to my Sennheiser HD555, which I thought were quite good already. I always thought there was not much difference between let's say a $100 headphone and a $500 one, and that only real audiophiles would be able notice the difference: people like Jake who can distinguish artefacts

SIMD and Mersenne-Twister

2011-02-05T13:18:00.000+01:00

Since 2007, there is a new kind of Mersenne-Twister (MT) that exploits SIMD architecture, the SFMT. The Mersenne-Twister has set quite a standard in random number generation for Monte-Carlo simulations, even though it has flaws. I was wondering if SFMT improved the performance over MT for a Java implementation. There is actually on the same page a decent Java port of the original algorithm. When

XORWOW L'ecuyer TestU01 Results

2011-01-12T20:26:00.002+01:00

Nvidia uses XorWow random number generator in its CURAND library. It is a simple and fast random number generator with a reasonably long period. It can also be parallelized relatively easily. Nvidia suggests it passes L'Ecuyer TestU01, but is not very explicit about it. So I've decided to see how it performed on TestU01. I found very simple to test a new random number generator on TestU01, the

The CUDA Performance Myth

2011-01-03T16:07:00.002+01:00

There is an interesting article on how to generate efficiently the inverse of the normal cumulative distribution on the GPU. This is useful for Monte-Carlo simulations based on normally distributed variables. Another result of the paper is a method (breakless algorithm) to compute it apparently faster than the very good Wichura's AS241 algorithm on the CPU as well keeping a similar precision.

Firefox 4 Is Great

2010-12-22T16:03:00.000+01:00

I temporarily abandonned Firefox for Chrome/Chromium. I am now back at using Firefox as Firefox 4 is as fast or faster than Chrome and seems more stable, especially under linux. Also it does not send anything to Google and there is bookmark sync independently of Google. I am impressed that Mozilla managed to improve Firefox that much.

Another Look at Java Matrix Libraries

2010-11-29T12:45:00.003+01:00

A while ago, I was already looking for a good Java Matrix library, complaining that there does not seem any real good one where development is still active: the 2 best ones are in my opinion Jama and Colt. Recently I tried to price options via RBF (radial basis functions) based on TR-BDF2 time stepping. This is a problem where one needs to do a few matrix multiplications and inverses (or better,

Java enum Is Evil

2010-08-12T17:32:00.000+02:00

Before Java 1.5, I never really complained about the lack of enum keyword. Sure the old enum via class pattern was a bit verbose at first (N.B.: Java 1.5 enums can also be verbose once you start adding methods to them). But more importantly, you would often use the table lookup pattern in combination. The problem with Java 1.5 enum is that it is not Object-Oriented. You can't extend an enum, you

A Very Interesting Feature of Scala

2010-08-07T12:35:00.001+02:00

I tried Scala a few years ago. There are several good ideas in it, but I found the language to be a bit too complicated to master. But I recently stubbled upon a paper on Scala generics that might change my mind about using Scala. Scala Generics used to work in a similar way as Java Generics: via type erasure. One main reason is compatibility with Java, another is that C++ like templates make

Street Fighting Mathematics Book

2010-07-28T14:25:00.000+02:00

The MIT has a downloadable book on basic mathematics: Street Fighting Mathematics. I liked the part focused on the geometrical approach. It reminded me of the early greek mathematics. Overall it does look like a very American approach to Maths: answering a multiple choices questions test by elimination. But it is still an interesting book.

Bye Bye Firefox

2010-07-21T15:30:00.000+02:00

I have been a long user of Firefox, mostly thanks to the adblock extension. But recently, Firefox decided to change the way arrows work on the web pages, they don't make the page scroll anymore. Meanwhile Chrome has now a good adblock plugin (that filters ads on load, not after load like it use to be) and is really much much faster than Firefox. So there is no more reason not to use it. Hello

Diffusion Limited Aggregation Applet

2010-06-09T14:05:00.000+02:00

Yes, I wrote an applet. I know it is very 1990s but, amazingly, it still does the job quite well. Ok, next time I should really use Flash to do this. The Applet simulates Diffusion Limited Aggregation as described in Chaos And Fractals from Peitgen, Juergens, and Saupe. It represents ions randomly wandering around (in a Brownian motion) until they are caught by an attractive force in

Java & 3D Surface

2009-12-18T16:07:00.003+01:00

I have been looking all around the web for a Java library that can draw a simple 3D surface. And I did not find any. Most charting library, including the well known JFreeChart, can only draw 2D charts. I am quite shocked that something that has been in Excel for 15 years is still not available in Java. And it's not easy to make your own.

double[][] Is Fine

2009-11-26T14:51:00.005+01:00

In my previous post, I suggest that keeping a double[] performs better than keeping a double[][] if you do matrix multiplications and other operations.This is actually not true. I benchmarked 3 libraries, Colt (uses double[]), Apache Commons Math (uses double[][]) and Jama (uses double[][] cleverly). At first it looks like Jama has a similar performance as Colt (they avoid [][] slow access by a

The Pain of Java Matrix Libraries

2009-11-26T09:17:00.002+01:00

Looking for a good Java Matrix (and actually also math) library, I was a bit surprised to find out there does not seem to be any really serious one still maintained.Sure, there is Apache Commons Math, but it is still changing a lot, and it is not very performance optimized yet, while it has been active for several years already. There is also Java3D, it does Matrix through GMatrix, but not much

Java Calendar Is Broken On JVM Upgrade

2009-08-19T13:47:00.005+02:00

We ran into an interesting issue with TimeZone and Dates. If you print the same date on different JVMs, it might show a different printed date.The reason behind this is the daylight saving time conventions. An old JVM won't necessarily have the same daylight saving time for a given TimeZone than a latest JVM, and therefore will interpret the date differently.Here is the output of a very simple

Implicit Finite Differences Method For Pricing Barrier Option

2009-08-17T12:04:00.004+02:00

While trying to price a simple knock down and out barrier option, I encountered several difficulties I did not expect with the implicit finite differences method. The explicit method has less issues with barrier options pricing. I will show here what the tricky parts are and why explicit seems simpler in this case.The full article is here (pdf) or here (html) (the later is not very well formatted

Pulseaudio Nightmares - Pure ALSA to the Rescue

2009-06-27T18:19:00.002+02:00

In the latest stable Ubuntu (9.04), pulseaudio still does not work reliably on my hardware (intel HDA with digital SPDIF out). I upgraded to 9.10 and had even more problems. Sound always worked on boot, but often broke down after a while. And I could not find easy ways to make it work other than rebooting... Killing/restarting pulseaudio, looking at the processes using snd did not work.One thing

Java int Overflow Behavior

2009-06-15T16:15:00.003+02:00

A coworker recently asked me if there was a guaranteed behavior in the case of int overflow. He gave the specific example on:can we rely that int x = Integer.MAX_VALUE + 1 is the same for every JVM on any platform?I thought the answer would be easy to find in the Java specifications document. But I was wrong. It is not clearly defined.I found a trick that suggests this behavior is indeed standard

Static Fields and Inheritance

2009-06-15T16:02:00.002+02:00

Someone asked me recently to find out the real reason why the code from this thread fails. This is a fairly bad code, and not even a very good way to point out the problem. But the question is nonetheless interesting.class Toto extends TotoParent{ final static Toto a = new Toto ("a"); public Toto(String a){ super(a); }}import java.util.ArrayList;import java.util.List;public abstract class

Benchmarking Languages Is Difficult

2009-06-03T16:53:00.002+02:00

I often looked at the famous computer languages shootout for fun. Recently I noticed they had the infamous thread ring test. I posted not very long ago several blog entries about it showing how silly this test was.Looking at the existing Java implementation for the test I decided to try to submit the tricky one using a pool of thread, and pooling message processing rather creating 1 thread per

Cholesky & Jakarta Commons Math

2009-05-15T19:01:00.003+02:00

In Finance, Cholesky is a useful way to decompose Matrix. It is not so simple to find a BSD licensed code using cholesky (most of them are GPL like this one). There is one in Apache Commons Maths library, which is a very interesting library. However for performance, it is still not very practical for some things like Cholesky.Looking at the source one can easily understand why. I did a small (

Hull American Option Price Fallacies

2009-05-15T16:01:00.002+02:00

Hull says American put is best exercised immediately and american call is optimal at expiry like a european. Is this really true?At first it seems really clever and model show clearly this. But if we change the market assumptions only a tiny bit, everything falls down.I could not detail everything in a blog post so I created a static web page about it. Everything was produced in Java using

On Quasi Random Numbers - MersenneTwister vs Sobol precision in Asian Option Pricing

2009-05-05T15:02:00.002+02:00

While starting a side project that does Monte Carlo pricing in Java (http://code.google.com/p/javamc/ - nothing yet there I am waiting for Mercurial repository support), I wondered what was the importance of quasi random numbers versus more regular pseudo random numbers in Monte Carlo simulations.This brought me to read more carefully several books about Monte Carlo and Finance (Haug Option

Java Logging Still Crap in 2009

2009-04-24T15:01:00.002+02:00

When java logging API was first introduced in JDK 1.4 in 2002, it caused quite a lot a fuss around, with everybody asking "Why did not they just include Log4j instead of creating their own bastard child?".I remember having looked at it very shortly before continuing using Log4j on all projects I have been involved with.Today, while doing a very small project, I tried once more to use java logging

Bachelier vs. Black

2009-03-23T17:58:00.003+01:00

Black and Scholes gives a strange result for the price of a binary option under high volatility. You will learn here how to simulate a stock price evolution using Java, and how to show it using JFreeChart library. It starts with more complex concepts (don't be afraid) and goes done towards simpler things.I could not write all that in a blog format, so I created a old HTML page about it here and

Linux Audio State = Miserable

2009-03-19T12:39:00.003+01:00

There are lots of programs for playing MP3 under linux, a few dealing decently with big libraries. But when you start looking for a program that does crossfade well and manage big libraries easily - there is nothing.Rhythmbox does some crossfade, but crashes when you move manually in the song. Audacious does some crossfade but regularly crashes with crossfade plugin.The real alternative are AIMP2

Senior Developers Team Productivity X4 (from MS Research Paper)

2009-02-10T10:44:00.004+01:00

There is a very interesting MS Research paper about test driven development (TDD). It is one of the only real study about it that I know of. The paper conclusions from experiments over 4 TDD teams vs 4 traditional teams is:"TDD seems to be applicable in various domains and can significantly reduce the defect density of developed software without significant productivity reduction of the

The End Of Rings Around Plain Java - A Better Concurrency Test

2009-01-15T15:54:00.002+01:00

In my previous post, I was wondering why single thread was faster. D Andreou gave the correct explanation: as we send only 1 start message and as each node only send 1 message to the next one, there is always only 1 message being processed. So the test is optimum on 1 thread. It does not make much sense to make a multithreading benchmark on a problem that is fundamentally single threaded. His

Object Oriented Analysis And Design with Applications Book Review

2009-01-08T17:24:00.001+01:00

A while ago, I had a comment from someone implying I knew nothing about OO programming because I had not mentioned (and therefore read) Object Oriented Analysis And Design with Applications from G. Booch. I was intrigued by such a silly comment and decided to look at this book that was considered as the bible of OOP. Well, I don't find it that good! But I don't find the bible particularly good

Running Rings Around Plain Java - The Killer Code

2009-01-08T13:21:00.005+01:00

I wrote my previous post too fast. I found a very simple change that increases the speed x6!The idea is too process messages in a ThreadPoolExecutor. As my Nodes are Runnable, I just needed to initialize a common ThreadPoolExecutor, and in a sendMessage, execute the runnable each time.Here is the full code:public class OptimizedRing { private ExecutorService executor; public static void

Running rings around plain Java

2009-01-08T12:26:00.002+01:00

Alex Miller has a very interesting test of Actors. He finds out Scala performance is relatively low compared to Erlang, and Kilim is very near Erlang. But Kilim code is the most difficult to read in the lot.I thought it would be simple to just do the same test in plain Java. I wrote the code for it duplicating the scala logic using Threads instead of Actors.public class

More Double Troubles

2009-01-06T12:12:00.004+01:00

We saw in a previous entry how one has to be careful with Double.NaN. Today we will see how regular double can cause problems. By the way the NaN issue was not Java specific and this issue is also general in different programming languages.A coworker was shocked that in Java (I was a bit surprised he saw that only today, but it is true it can be surprising that such a simple thing does not work

Java Programmers Are Idiots?

2008-12-17T20:16:00.003+01:00

My brother just sent me a funny quote. I don't know if it is true or not:entwickeln Sie lieber überzeugende Lösungen anstatt viele Stunden mit Coding zu verbringen? Ist Ihnen die Produktivität Ihres Teams wichtig?Mark Driver, *VP Research von Gartner*, kommentierte kürzlich:"Here’s a simple equation. In terms of mental fortitude...*1 Smalltalk developer = 2.5 C++ developers1 C++ developer = 1.5

Double.NaN Is Evil

2008-12-09T16:23:00.002+01:00

I don't know what Sun had in mind when creating Double.NaN number. It is very inintuitive to use. I am sure every single developer out there fell in the trap of trying to find out if a double was NaN or not using:Double.NaN == myDoubleThis does not work (I don't know the real reason why), one has to use:Double.isNaN(myDouble)Not intuitive!

Grails Spring Union Not Surprising

2008-11-27T17:18:00.003+01:00

Looking out at some old post. I found out I was not far from the truth in January 2008 when I stated:"In 2008 the Ruby On Rails mentality will continue to prevail. In the Java world, Grails is the most likely to benefit from it. (...) It could also be something based around Spring as their current MVC solution is not very good and very old fashioned."I don't think I will be right with the

Java Is Dead

2008-11-21T20:24:00.003+01:00

These days, I have the feeling that Java is dead. Even if, or maybe because I have used Java so much in the past 10 years, I have this feeling.In 1998 Java was revolutionary. It was a very simple to learn object oriented language with modern concepts and familiar syntax. Furthermore the standard library had neat features like internet networking and it could be integrated in the browser. All this

Why ArchLinux Is Better Than Ubuntu

2008-11-14T10:41:00.003+01:00

It has been now a week since I have installed ArchLinux on my home computer. I daily use Ubuntu 8.10 at work.Since the Ubuntu upgrade from 8.04 to 8.10 I have had problems with my Xorg settings. I just found out the nvidia-settings utility does not manage to save the configuration anymore. So I have to lookup on google and try to fix it. And that annoys me. That annoys me because the promess of

KDE 4.1.3 (again) on ArchLinux

2008-11-08T15:54:00.002+01:00

I tried another silly thing with Linux, ArchLinux. The setup is quite rough as you have to edit many config files manually. But if you know a bit your way around it takes only a few hours to have everything running well. The installation manual on the wiki is detailed enough to correct all eventual mistakes humans do.I decided to try once more KDE 4 on it, as at first it was just a silly

Stupid Programmer Interviews

2008-09-17T10:56:00.001+02:00

I have read a blog post a few days ago about someone thinking a good programmer interview question was: How does a hash table work?While it is a very interesting question, I doubt many programmers (even relatively good ones) can answer that question. If I look back and think of all the employees in all the companies I have known, I can count on one hand people that can answer that question. I can

The Art of Multiprocessor Programming Book Review

2008-09-11T19:32:00.001+02:00

I don't remember why I started to subscribe to the Java concurrency-interest list. I find that overall, it is an excellent mailing list.There was a post at one point about the Dante Inferno's problem. It triggered my attention, so I decided to buy the book the post was referring to, The Art of Multiprocessor Programming by M Herlihy and N. Shavit. The books starts with the basics, and is very

OO Desillusion

2008-08-28T17:00:00.003+02:00

I have read many inspiring books about object oriented programming. I find B. Meyer Object Oriented Software Construction one of the best in the lot. B. Meyer tries to explain in a progressive way why OO is better, by introducing it bit by bit. I have read different related design patterns book, the GoF one, Martin Fowler ones. I have been programming Java for about 10 years now. And yet, today,

Linus vs OpenBSD

2008-07-17T11:38:00.003+02:00

Today's popular story is Linus Torvalds message to OpenBSD where he writes: I think the OpenBSD crowd is a bunch of masturbating monkeys Beside that provoking sentence he has a valid point. Security bugs should not be more important than other bugs. Too often, management and psychology encourage making security bugs a very important issue and security people VIPs. I have seen this over and over.

Suse 11 with KDE4

2008-07-17T11:38:00.001+02:00

I was very disappointed by KDE 4.0 when I first tried it on an ubuntu machine. It was just unusable. I would not have even considered it as a beta. I changed the system on my home laptop because Ubuntu with KDE 4 was there. I decided to go for something more roots. I had good memories of Gentoo when I tried it some years ago. Maybe I just became too old to appreciate it anymore. But after

Java Compilation Performance / Processor Speed

2008-07-01T19:50:00.001+02:00

I just found out my laptop was faster in default settings than my home desktop to compile a resonably sized project (5 min vs 6 min). I was surprised as I thought the disk in the desktop would make a big difference. The processor in my desktop is not that great (simple pentium e2180). My laptop has a 2ghz core2duo processor. In Ghz processor are of the same speed.I tried to overclock my home pc

Firefox 3

2008-06-18T11:26:00.001+02:00

I tried Firefox 3 twice before, while it was in alpha and beta. I was not impressed at all, it seemed buggy (normal for alpha) and I found the new location bar behavior unintuitive. It did not seem that much faster either. So I always quickly went back to Firefox 2.I tried again recently, funnily, because of a bad Kernel update. One day, after a kernel update, my laptop started to run only at a

Trying Google AppEngine

2008-06-17T19:26:00.004+02:00

I finally took some time to try Google AppEngine. It used to be easy to find free PHP hosting around 2000. It became a rarity. So writing small experiments for free on the web was difficult. Experiments are back thanks to Google with their AppEngine. Many aspects of it are quite interesting and show where they focus.First it is all Python. It makes sense as I believe Guido v Rossum, Python

Option, Futures and Other Derivatives Book Review

2008-06-16T17:06:00.001+02:00

Option, Futures and Other Derivatives is by far the most popular book in finance. You will find it in every finance company, on many desks.It is a very good introduction for people not familiar with standard financial products. This kind of book is unavoidable to understand the basis. It goes also beyond with the chapters on pricing and hedging. These 2 chapters make one understand many other

Structured Equity Derivatives Book Review

2008-06-16T16:55:00.003+02:00

If one has to learn about equity derivatives, beside the classic Option, Futures and Other Derivatives from Hull, Structured Equity Derivatives by Harry M Kat is a must read.His ideas are presented in a software developer friendly way, as his goal is to show how different equity derivatives products are behind the scenes, very similar.I enjoyed the variety of exotic products presented and the

Fedora Linux & Apple Bluetooth Keyboard

2008-06-05T20:05:00.003+02:00

It took me a long time to have the Apple Bluetooth Keyboard (slim aluminium model) working well with Fedora 9. Thanks to the Ubuntu documentation, it is quite easy to establish a connection manually through hidd commands. It was unfortunately much more difficult to have it automatically recognized and not disconnected after a few minutes without use.The following configuration should work with

DecimalFormat Is Broken

2008-05-14T18:19:00.002+02:00

A friend of mine recently noticed that the good old DecimalFormat class is "broken". If you try to parse a string that is not a number but is starting with a number, the DecimalFormat.parse will return what it managed to parse.The correct behavior should be to throw a parse exception IMHO. Judging from an old post in the Sun bug tracker, The folks at Sun don't think it really is, they call the

Using MiG Layout For Better Swing Development

2008-04-29T18:27:00.003+02:00

I have forgotten a few libraries in my Better Swing Development article, and notably MiGLayout.GridBagLayout is too verbose, and still feels too clumsy. This is why a while back I wrote a small tool to help visualize various GridBagLayouts for people who are not used to it. But it would have been much simpler to use a better layout instead.MiGLayout is good, I managed to have good results without

_the_ Google 1998 paper

2008-04-25T14:22:00.002+02:00

I have just read "the anatomy of a search engine" from S. Brin and L. Page. For those who don't know, it is _the_ Google paper. I have read other google labs papers in the past. What I like in this one is that you can follow how they came into having the Google ideas, how they assembled their ideas.I should have read that a long time ago.

Fedora 9 Already Stable

2008-04-25T11:33:00.002+02:00

I "upgraded" my home computer to Fedora 9. "upgraded" because I reinstalled the OS instead of using the upgrade procedure. I have had so many issues with "partial" upgrades in the past (with any distro).Although it is the preview/RC1 version, Fedora 9 is already as stable as a release IMHO. No issues so far, it feels more polished than Fedora 8. OpenJDK 1.6 is there. Firefox 3 is there. Not a

SwiXml Review

2008-04-24T12:19:00.005+02:00

Externalizing the screen layout is a natural step for many applications. It can be because a customer might want a slightly different presentation, or just for the sake of clearly separating layout code, or for using a kind of screen generator. Back in 2003, I wrote a small utility to help with GridBagLayout, nothing fantastic, but there was the feature of saving a generated layout in XML (or

Better Java Swing Development

2008-04-17T20:55:00.000+02:00

It has been a while since I have looked at the different options for building GUIs in Java. I like the approach taken by Eclipse, they provide not only GUI components, but a complete GUI application framework. Several years ago, I have stolen ideas from it (how they manage plugins) and applied it for Swing applications. This worked out quite well. The Netbeans platform now offers a more

Fedora 8 vs. Ubuntu 8

2008-02-28T14:23:00.002+01:00

I had the bad idea of trying (K)ubuntu 8.04 on my home computer. It worked for a few days, but as Ubuntu 8 is still in alpha, changes tend to break everything easily. At one point Wine stopped working, then the DVD, then the sound. I had crashes with USB plug/unplug. It was time to go back to a stable distro. I went back to Fedora 8. I found out that I had missed some positive sides of Fedora 8

Windows Vista Is Crap!

2008-02-08T17:59:00.001+01:00

It has been already 1 year since Windows Vista is out. In my new company, I had a new computer with Vista on it. I quickly installed Ubuntu in dual boot. I was happy with Ubuntu for my work, until I received many Excel files OpenOffice was not able to read properly. I decided to give a try to Vista. My first impression of it when I had the computer was quite negative. I was not able to find

The 2008 Java Web Framework

2008-01-22T11:50:00.001+01:00

One of my first web framework was a custom one, based on the book Web Development with Java Server Pages. That was in 1999, when Struts was not yet known. But it was web-MVC, very near from what Struts gave later, without the custom tag stuff (custom tags were not yet part of JSP specifications). Until 2007, Struts was IMHO the most used web framework and the default choice, even though many

KDE4 Still Not Ready

2008-01-18T19:08:00.001+01:00

I tried KDE4.0 last week, when it was everywhere in the news. I was very disappointed.I have a long experience of trying beta software, not well known software. I have used Linux since 1998 (partly). I have even used windows beta at one point. And I have seen nothing as crappy as KDE4.0 release. It is not usable at all. Now I can understand what are KDE motivations to do such a bad release. It

Fedora 8 - The Comeback

2007-12-23T02:28:00.000+01:00

My previous post about Ubuntu Gutsy vs Fedora 8 was weak. It is difficult to find a very good distro. Depending on the computer, I have had different experiences. On some computers, Ubuntu really shines and work with minimal tweaking. On some others, Ubuntu is unstable/does not handle wireless correctly and Fedora is much more stable.The main issues I can see with Fedora 8 are:- LVM by default. I

Haskell Fibonacci Revisited

2007-12-12T17:08:00.000+01:00

Recently, there was an interesting post about Haskell performance and Haskell parallelization showing Haskell could outperform C on a simple Fibonacci example.A friend of mine, Peter (that I seem to manage to constantly piss off) thought about it on another level, saying you could achieve a _MILLION_ times better using a direct formula in C or Java, the Binet formula.I decided to try as the

Ubuntu 7.10 vs Fedora Core 8 - Gutsy vs Werewolf

2007-11-20T16:23:00.001+01:00

I was pretty happy with Ubuntu 7.10, but when Fedora 8 came out I decided to give it a try. Last time I tried it it was Core 2 or something like that, and it was NOT good.At first Fedora 8 looks quite good, has a good Live CD install, reminiscent of Ubuntu. The positive side is that it is based on the latest Kernel. It manages my Thinkpad T42 very well (suspend, hibernate work). But after a few

Apache DbUtils Completely Useless

2007-11-02T17:17:00.001+01:00

I am disappointed about the Jarkarta Commons DbUtils project. I give a link to it, because it's a bad project (even if written in clean code). It is very simple, but it really does not do much for you. I was looking for a very simple abstraction of JDBC. I thought bringing Spring in my project would be overkill. After trying DbUtils, I think again. It does not help. It does not handle frequent

I fell in the trap of Boolean.getBoolean()

2007-10-12T16:10:00.001+02:00

I was struggling to find a bug in a very simple application, it ended up being something as simple as using the damned Boolean.getBoolean("true") call instead of Boolean.valueOf("true").booleanValue() call. The Boolean.getBoolean method is something you almost never need to use, as it checks if a particular system property is true or false. There is a similar method for Integer.getInteger, and a

Fast Web Development With Scala

2007-09-25T14:02:00.000+02:00

I am currently experimenting with Scala. It seems quite convenient for web applications. Using Tomcat, it is possible to have a very productive developer environment.Here is a sample Embedded Tomcat you can start in a Scala project: import java.io._;import org.apache.catalina._;import org.apache.catalina.startup._;object TomcatScalaServer { val CATALINAHOME

2 Months of Ubuntu on Mac Mini

2007-08-27T23:48:00.001+02:00

I am finally happy with my OS. I had previously some complaints about MacOs X and the Mac Mini. It is now over, with Ubuntu, I am very happy of my quiet system. I use Quod Libet for Audio, it has similar interface as iTunes, with more features (ability to play most audio formats). I chose Quod Libet instead of the standard Rhythmbox because of its practical mp3 tags handling. This also means

Spring Web Services, Finally!

2007-08-23T11:22:00.001+02:00

Spring Web Services seems to be the technology I have been looking for recently. I am not a Spring bigot (too XML oriented), but here the Spring folks have something right. I used to work with Web Services the simple way: create a java class (or EJB), expose it as Web Service through Axis or RAD, generating the WSDL in the process. And then a client would just be the reverse, take the WSDL, use a

Original Pattern: ServletRequest in ThreadLocal

2007-08-02T12:07:00.001+02:00

After seeing Scala had elements of Erlang through Actors, I decided to take a closer look at the language. There is an interesting new web framework in Scala, called Lift. One drawback of Lift is that it seems to be very cutting edge and not that easy to grasp. While reading its source code, I stumbled upon a strange pattern: Storing the ServletRequest in a ThreadLocal .I had not seen that

Vim setup

2007-07-27T16:13:00.001+02:00

Here is my Vim setup information for referencein .vimrc or _vimrc, add at the beginning: set langmenu=en_US.ISO_8859-1set gfn=Bitstream_Vera_Sans_Mono:h9:cANSIcolorscheme oceandeepFirst line is to avoid menus in French.The font (you can find here) is simply the best programmer's font.oceandeep mode can be found here .

Why Eclipse Is Better

2007-07-27T14:37:00.001+02:00

Initially I adopted Eclipse instead of Emacs because it was more powerful to search code, and it allowed refactoring. I regularly tried other IDEs but always end up back to Eclipse, even though there has been less big improvements in Eclipse in the past years (but lots of small ones). I just saw today that Eclipse allowed programmatic refactoring. Now that's something quite amazing, and I don't

Tapestry5 vs Wicket: 1 - 0

2007-07-11T12:49:00.001+02:00

Getting started with Tapestry 5 is easier than with Wicket 1.3. Some readers will complain that it is again the view of someone who has no deep knowledge of either Tapestry or Wicket. But I think it is important for projects to be easily accessible to developers. Wicket seems to have more buzz around these days, and has a detailed wiki with plenty of useful information in it. But that's the

NetBeans 6.0M10 out without announcement yet!

2007-06-30T07:15:00.001+02:00

I just found it while browsing netbeans website, here is the link. Netbeans is starting to be much more interesting that it used to be before 5.5, even though shortcuts are a pain, because so different from most other editors, and not always defined for important tasks. I like the all integrated feeling without plugin and slugishness by default.

Use ORM For Better Performance

2007-06-12T12:59:00.001+02:00

This is not something I would have though a few years ago. It is something I learnt after working on many different projects, some using an ORM layer like Hibernate, Entity EJBs, or JDO, some using JDBC approach via Spring Templates or custom frameworks. Many projects that use ORM have performance problems, that don't seem that common with projects using JDBC. But the size of the database model

People Using Spring, EJBs Don't Know Basic JDBC

2007-05-30T12:03:00.001+02:00

I recently found a bug in software we are developing. I traced it and found the root was improper JDBC handling. The application is written using EJBs, Spring and plenty of other relatively complex technologies. I was surprised that developers who were able to use all those technologies had no understanding of basic JDBC. They fetched all the data (including double, decimal numbers) from the

Wizards Bad For Productivity

2007-05-16T14:56:00.000+02:00

IBM RAD comes with many wizards, to create EJBs, to create Web Services, do struts mapping... They are quite well done, making EJB < 3.0 usable, and Web Services look simple.But wizards sucks at:typos correctionrepetitionBut when you do a typo in your wizards, then all the files generated/changed are wrong, and you don't necessarily know if you can just do a search and replace. Plus you don't

Less Productive With Maven2.

2007-04-29T17:10:00.000+02:00

My first trials of Maven were failures. As I am stubborn, I tried again, on a new project, a quite simple one. It works, but it makes some easy things overkill. And the default way of using it makes a developer lose lots of time.If I have a project with common classes, a standalone app, and a web app, then logically you do 3 projects, 2 of them depending on the common one. That's how the default

How to Build Good Software? Good network connection

2007-04-27T12:40:00.000+02:00

Not having good internet connection can be problematic to download new libraries, read or search for documentation on development subjects. But not having a good internal network connection is killer of productivity. It means sometimes not being able to access integration, preprod or even production environment, or ssh session not responding in the middle of an action. As software makes an

How to Build Good Software? Private office, again

2007-04-25T15:01:00.000+02:00

Apparently it's more a habit of French companies to have big open spaces with no separation at all between people. There is nothing more annoying than having people in conference call in front of you while you are trying to work on something completely different. French people forgot the cubicle part in the American open space idea. So sometimes the room is just a big mess, everybody being able

How to Build Good Software? Welcome newcomers

2007-04-18T20:17:00.000+02:00

Some companies do it naturally, some really don't. In small companies, it is almost natural, people will make a newcomer productive very quickly. In a big company it's not the same game.Some important points are:Computer ready the first day, well sized (right ram, right power, developers are not MS office users), right OS. I had experience with having not the right amount of ram, not the right

Project Estimations And Fibonacci Sequence.

2007-04-13T13:01:00.001+02:00

I was recently in a meeting where use case complexity was estimated using numbers in the Fibonacci sequence. I was surprised by the choice of the Fibonacci sequence. Why not any sequence? Why a particular one? I googled and found the culprit, Mr Mike Cohn in his book Agile Estimating and Planning. It's actually not a bad sequence to choose, since the scale is increasing constantly, so by

How to Build Good Software? Use a bug management software, really.

2007-04-13T10:56:00.000+02:00

This will seem obvious, unfortunately, when people are involved, nothing is that obvious. It's not because you setup a bug/feature management software that people will use it. You have to force people to go through the bug management software each time they want something fixed. If you don't do that some people will keep sending incomplete mails, or worse call you to get something fixed, that

How to Build Good Software? Have a good build process

2007-04-12T09:54:00.000+02:00

Important points are: standard code hierarchy, automatic download of dependencies, a distribution command with versioning support and source control interaction, a simple command to build each part of the project. In Java best candidates are a sophiticated ant build, or maven2. Maven2 is quite good since it forces you to do some of those steps, even though I think ant can't really be avoided for

How to Build Good Software? Private Office

2007-04-11T10:52:00.000+02:00

In an open space, people keep on coming to discuss various issues with various people, issues that have nothing to do with your work. You end up either being distracted, or annoyed by the increased noise level. Apparently at Microsoft, they have private offices for each programmer. It might be extreme, paradoxally not in the XP (extreme programming) sense, but it is much better than open space

How to Build Good Software? Lay Off Quickly.

2007-04-10T11:12:00.000+02:00

If you have to lay off in your job, do it quickly. I don't understand companies that want to keep someone as long as legally possible when this someone wants to leave. First the employee won't be as motivated, but more importantly, you will continue to train that person to your company's software and ways of work. This would be much better used on another person, that will stay in the company.

How to Build Good Software? Talk to people, especially the ones you don't know well.

2007-04-06T17:02:00.000+02:00

Someone modified a simple launch script on a integration machine. This pissed off the author of the script. Why? Just because the guy who modified the script never worked before with the author of the script. If only the author had been notified verbally or by mail of the modification, he would have been happy. Furthermore this would increase the quality of the change since the new guy might have

Find Grep And Vi Keys Small Memo

2007-04-05T18:48:00.001+02:00

I tend to forget this now and then to grep on a specific list of files: find . -name "*.xml" | xargs grep "iwantthis"And I also tend to forget the vi keys. Small extract: h - move left one characterj - move down one linek - move upl - move right$ - go to the end of the current line0 - go to the beginning of the current lineG - go to the last line in the file15G - go to line 15control-F - forward

How to Build Good Software? MS Press Code Complete says Measure twice, cut once

2007-04-05T14:14:00.000+02:00

I am starting a series of posts about software construction, based on good and bad experiences while working for my many employers."Software construction (a.k.a. architecture), is the only activity that's guaranteed to happen on every project". It is not rare that projects or new features are abandoned either because they are too costly, or because they are not needed anymore, or because they are

Java Concurrency In Practice Book Review

2007-02-14T16:33:00.001+01:00

My reference book on Java concurrency is Doug Lea's Concurrent Programming in Java: Design Principles and Patterns. He is one of the authors of this new book, Java Concurrency In Practice. There is also Joshua Bloch, author of Effective Java, that many people love (but I am less a fan of it, even if I would recommend it to Java newbies), and author of Java Puzzlers, that I found more fun.With

Why are you not using Entity EJB 1.1?

2007-02-07T16:38:00.001+01:00

I am currently quite busy learning about Websphere Commerce. I was surprised to notice that they still use Entity EJBs 1.1. My experience was that many companies turned away from Entity EJBs, sometimes from the beginning, preferring TopLink or Hibernate (later). I know that Entity EJBs are more heavy to use than Hibernate, but with the proper tooling support, it's not really a big issue. Are

Switching to Windows

2007-01-25T01:04:00.001+01:00

That's it, I have done it, the unthinkable. I have switched from MacOs X to Windows XP. My idea was first to install Ubuntu on the Mac Mini, but if you want to keep the Mac Os X install, the methods I have read on the web required to use bootcamp. At around the same time I was annoyed by problems I had with bluetooth and Skype in MacOs. So, with bootcamp installed I decided to give a try to

Social (Web) Revelation: Tags Are Lame

2007-01-16T10:26:00.001+01:00

I had a revelation yesterday while thinking about del.icio.us, the most well known social bookmarks site. I find out that I almost never use my tags, and I am often not satisfied by results when I search using tags. What use can you make of 100s of tags? in the end only less than 10 are usable to classify very different stuff. And even then compared to a search it's not a much useful