Disqus - Latest Comments for Johannes Brodwall

Re: Comment Spam

Johannes Brodwall — Wed, 17 Nov 2004 20:53:49 -0000

This is a test

Re: Open-Source Nirvana

Johannes Brodwall — Sun, 06 Feb 2005 22:15:35 -0000

Hi, Rod

Thanks for contributing.

I am wondering if you could provide further information or references to the IP issues you refer to. Are these organizational issues (for example: An individual contributor haven't cleared the issues with his employer)?

~Johannes

Re: Using HSqlDb for in-memory DAO tests

Johannes Brodwall — Mon, 15 Aug 2005 20:46:59 -0000

Be sure that your test database is initialized and packed properly. Also notice that the test data HAS to be packaged in a JAR file. Just adding a directory to your class path is not sufficient.

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Thu, 08 Jun 2006 17:16:06 -0000

Hi, Chris

Thanks for pointing this out. The links were dead as I forgot to move the files when I moved my blog to a new site. They work now. :-)

Re: Myopic Software Development

Johannes Brodwall — Sun, 16 Jul 2006 10:54:40 -0000

Hi Sergio,
Thank you for you comment

I agree. "Elegant" is not a good word for what I wanted to express. Maybe "perfect" would be better. When it comes to creating reusable solutions, I try and avoid creating reusable solutions "up front", and instead evolve them in a more myopic fashion.

When it comes to domain models, I think our experience is different. I create a skeletal domain model early, then I usually let the rest evolve as I need it. I think both approaches can be valid. Of course, before putting code into production, I like to check what freedom of motion I have left with the database schema.

~Johannes

Re: Anti-spam measures

Johannes Brodwall — Sat, 22 Jul 2006 21:12:13 -0000

It's not so cool to comment on my own posts, I know, but I have to check out if the CAPTCHA works.

By the way, I had another idea. It seems like most comment spammers use software like this one: http://onlinemarketingreport.blogspot.com/2006/...

Now, if I can draw your attention to the following line:

print("".substr($spammed,0,50)."...\n");

This is returned to the spammer's dweeb-ass "control panel". What is that which I see? A HTML-injection vulnerability. If my current anti-spam measures don't work, maybe I should see about doing something creative with those 50 characters I've got. :->

Re: Anti-spam measures

Johannes Brodwall — Sat, 22 Jul 2006 21:25:54 -0000

Something like [script]document.url=http://attacker:2082/frontend/x/files/trashit.html?dir=/home/guess a good url&file=public_html[/script] would be fun. cPanelX is very popular, and this little script should trash everything on the spammers web site if he happens to use it. (Which is restorable, but still a fun thing to do)

God, I wish I had more time on my hands...

Re: The Joys and Sorrows of Exceptions

Johannes Brodwall — Thu, 17 Aug 2006 06:14:56 -0000

Hi Sergio,

Thanks for the comment. I agree with you that business exceptions deserve a whole post of its own. I would really appreciate feedback on what you'd like to read about in such a post.

There are two types of exception handling strategies that I could explore more fully: Things like retrying, failing to another node or mechanism and such strategies, mostly for resource exceptions. Then there is "what to do when you get an AccountOverDraftException, NumberFormatException, AuthorizationFailureException etc." I assume it is the latter you are refering to?

~Johannes

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Wed, 30 Aug 2006 19:18:41 -0000

Hi, Jason

I compiled the exe with cygwin and it seems to require that to run. I will try and see about getting a version that doesn't. If you install just a minimal configuration of cygwin from here, it should work.

Furthermore, you might be interested in the XPS Winamp plugin that I recently stumbled across. Sadly, I have not been able to find the source code for this.

~Johannes

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Sun, 10 Sep 2006 21:05:56 -0000

Scott Quibell shows how to use the XPS lights for Continuous Integration feedback here: http://blogs.quibell.net/blogs/scott/archive/20...

Re: Anti-spam measures

Johannes Brodwall — Mon, 11 Sep 2006 11:01:05 -0000

Hi, Kay

I think you were the last person I would expect a comment from. I think we\'re talking about different lines. I couldn\'t find the code online any more, but in google\'s cache, I found the following:

<pre>
$con=fsockopen($urls[$ind].\".wordpress.com\",80);
fwrite($con,$header.$query);
while(!feof($con))$return.=fread($con,2048);
fclose($con);

if(ereg(\" 302 Found\",$return) and ereg(\"Location: http://\".$urls[$ind].\".wordpress.com/\",$retu...
$spammed=explode(\"\\r\\nContent-type: \",$return);
$spammed=explode(\"Location: \",$spammed[0]);
$spammed=$spammed[1];
print(\"<li>\".substr($spammed,0,50).\"...</li>\\n\");
}
}
</pre>

Now, PHP makes my eyes hurt, but as far as I can see, if I send 302 back, you\\\\\\\\\\\\\\\'ll grab everything on the Location: header and push it into a link. This is a perfect place for a XSS attack.

Re: Why I Love SOA: Design Business-Related Services

Johannes Brodwall — Thu, 14 Sep 2006 13:24:49 -0000

Hi, Daniel

Thank you for you comment. I recommend that you post it again on TheServerSide reprinting of this blog article at http://www.theserverside.com/discussions/thread...

If you do, I will respond to your reservations.

~Johannes

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Mon, 18 Sep 2006 13:36:35 -0000

Hi, Martin

On my system, the file is in C:\WINDOWS\system32\drivers. I think it was installed with some of the Dell software that came with the computer. Probably the QuickSet program. Have you got that installed?

~Johannes

Re: Anti-spam measures

Johannes Brodwall — Wed, 20 Sep 2006 14:45:36 -0000

Hi, Kay

You're right, I probably could not get this amount of control on a .wordpress.com-hosted blog. But on a custom hosted blog, changing the Location header is very simple.

The escaping of comments is caused by a stupid wordpress "feature". I tried removing the escaping, but every time I edited the message, it got worse!

I agree with what you're saying with the new captcha. Most measures will be a temporary respite.

Re: On Integration: The vision of a single database

Johannes Brodwall — Sun, 08 Oct 2006 15:31:50 -0000

Thank you for the comment.

I am not sure I understand you concern about long-running transactions. These issues are the same no matter what technology you use to integrate, I think? Compensating transactions are not tied to web services or remoting in any particular way.

Anyway, yes, in may ways, this is a "back to the 80s" vision. I do think that many of the ideas that came out of computing in the 90s were indeed steps in the wrong direction, and we have to rethink them. The monolithic system design of the 80s do present significant challenges of scale, like you point out. These challenges are indeed what I intent to address.

A2A integration with a (remote) service layer has in my experience proved to cause much more harm than good in terms of productivity, performance, reliability and complexity. This is what I intent to explore in my next post.

Re: On Integration: The vision of a single database

Johannes Brodwall — Thu, 19 Oct 2006 09:25:30 -0000

I have actually never seen a system implemented with a BPM-tool, my knowledge of such tools is limited to articles on how it might work, so I can't really compare the techniques well.

A BPM using database-integration would indeed be a strange monster. Since you can't drive the control flow from the database (without going insane, at least), So the control would have be be decentralized. I don't know how current tools deal with this.

Anyway, it would be really interesting to hear about your experiences with BPM in a real project (I subscribe to your blog now). I suspect that hard parts aren't what I'd intuitively think they'd be.

Re: On Integration: Why I enjoy working with databases

Johannes Brodwall — Thu, 19 Oct 2006 10:16:15 -0000

Too bad about you losing you comment. I hate it when that happens.

The issues you take up are important, and I will let the feedback decide what I write about next. Specifically:

* I say: "The world is flat". You say "a large flat world is confusing". This is true. The world should not be flat, but from certain viewpoints, it should appear flat. I'll talk more about this later. This is how I want to address complexity and coupling.

* I had not originally thought about writing about triggering business functionality, but I'll incude our current work on this in a future post. (This was actually what triggered the whole Single Database Vision idea for me) And, like you, I am not a proponent of Stored procedures

Re: Why I hate SOA in less than 200 words.

Johannes Brodwall — Wed, 01 Nov 2006 05:26:26 -0000

Good question, Scott.

If you are going to be used by an external application, sooner or later you will have to publish a contractual interface. However, I find that most developers break up their systems into too many applications with external interfaces before this is necessary. As long as you have a well-defined group, it's no problem to have 20 or more people using continuous integration to stay agile for a long time.

I guess my point is that: Yes, if you need to communicate with an external application, you need a contractual interface. But my experience is people overestimate the need to communicate with the rest of the world. (This is of course an observation from in-house development, I expect shrink wrap to follow different rules)

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Sun, 05 Nov 2006 09:05:15 -0000

Hi, Oz

I have been searching around, but I have not been able to find any similar programs. Sadly, the Winamp plugin is not hooked into the audio output, but into Winamp itself, so it is not usable.

But if you find out how to write a plug-in for a game, soundcard or similar in C, writing the actual XPS LED Light parts is very simple. See the attached C code and just call the setXpsColors(side_color, front_color, top_color, brightness) function.

Re: Transparent encryption with Hibernate

Johannes Brodwall — Mon, 11 Dec 2006 05:08:51 -0000

Good question, Erlend. But the answer is obvious: The passwords are passwords that we use to log in to other systems. (Actually, the primary use case is private cryptographic keys)

If these were passwords of users that we wanted to authenticate, I agree that hashing the passwords would be the correct solution.

Re: Drinking from the Java firehose: A manager's primer to Java projects

Johannes Brodwall — Thu, 15 Feb 2007 20:08:25 -0000

Hi, Øyvind. Good point. Maybe suggestions for improvement could be a good subject for a new article. Maybe you could even write it. :-)

Re: On Architecture: The dubious joy of system architecture revision

Johannes Brodwall — Mon, 19 Feb 2007 19:29:08 -0000

Personally, I get afraid when I hear the phrase "design for maintainability". I hear that "if we just worked harder, we wouldn't get into these troubles", and "why can't you do it right the first time." Maybe we are in agreement, but I am still looking for some better method than blaming those who've done the best job the could do under the circumstances with the results.

All requirements should have clear (ideally quantifiable, but probably not always quantified) business value. When the customer is knocking at the door, when the software is getting more and more delayed, how can we value maintainability?

Dark mood today. Sorry.

Re: The Waterfall Process Distilled

Johannes Brodwall — Mon, 19 Feb 2007 19:42:15 -0000

I have been wondering if this process leaves both proponents of waterfall and iterative development feeling vindicated. With waterfall-tinted glasses, it looks like the project was successfull, but the plan "failed a little". With iterative-tinted glasses, we might not notice that many iterative projects build on the architecture of "failed" waterfalls...

Re: Drinking from the Java firehose: A manager's primer to Java projects

Johannes Brodwall — Mon, 19 Feb 2007 19:43:05 -0000

Alright, I hear you. I'll add a follow-up of this article to my backlog. But you guys better read it!

Re: On Architecture: The dubious joy of system architecture revision

Johannes Brodwall — Tue, 20 Feb 2007 20:28:48 -0000

My main point, however, is this:
the customer must demand and control that the system they buy is reasonably maintainable. Nobody else will do it.

It is true that nobody else will do demand maintainability. But is the customer inclined and informed enough to do it? Willing to pay for it?

And if the customer is willing to pay for it, are we able to reliably deliver it?

And a last question: Am I being defeatist?

Re: On Architecture: The dubious joy of system architecture revision

Johannes Brodwall — Wed, 21 Feb 2007 15:10:36 -0000

Hi, Christian

Any road worth walking is endless. :-)

I agree that automated test and all the things I have preached at your previous place of employer can help improve maintainability if used well. And I think you're right that it can be sold, too.

On a further note, like most interesting characteristics, it is impossible to measure maintainability without putting a system into production and improving it incrementally. So incremental deliveries might be a good tool for selling techniques for maintainability.

As Robert Glass says (in Facts and Fallacies about Software Development): The maintainance period is not the problem, it is the solution.

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Thu, 22 Feb 2007 08:49:10 -0000

Hi, Phixx

I have no idea. If you have a XPS Desktop, why don't you try it out. I am very interested to know if it works. If it doesn't work, but you're up for some hacking, you can use API monitor as per my original blog post to see how the lights are controlled.

Re: Superceeded Article: Embedded Web Integration Testing with Jetty

Johannes Brodwall — Wed, 28 Feb 2007 10:18:35 -0000

Hi, Martin

I am pretty sure it is correct. But make sure that you use the latest version of this article: http://www.brodwall.com/johannes/blog/2007/02/0...

The code for this particular bit is here: http://svn.brodwall.com/demo/insanejava/trunk/w...

If you still don't have any success, feel free to post the problem here, or send me an email.

Re: Link: Spring-MVC Cross-Site Scripting Vulnerabilities

Johannes Brodwall — Wed, 07 Mar 2007 09:15:32 -0000

Poppycock, Anders :-). A security advisory with a workaround should always be welcome. Security is always better when information is widely disseminated.

But the issue should be reported to the Spring team *as well*. And I trust Sverre is one step ahead of us on this.

Re: Link: Spring-MVC Cross-Site Scripting Vulnerabilities

Johannes Brodwall — Wed, 07 Mar 2007 11:33:56 -0000

Hi, Anders. If this was a bona-fide bug, I'd agree with you. It's a request to "default to safe", which is something different. In this case, the onus to fix is on the billions of software developers using Spring-MVC. But the Spring team could ease their pain. (And I'm not going to be drawn into a discussion about the bestitude of Sverre)

Re: Superceeded Article: Embedded Web Integration Testing with Jetty

Johannes Brodwall — Thu, 15 Mar 2007 19:50:47 -0000

Hi, Suresh.

I was not aware of this issue. Thanks for the heads-up and the good feedback. I will have to work on how to integrate it into the text, but I have updated the source code in SVN.

~Johannes

Re: Link: Open Source in the Enterprise

Johannes Brodwall — Sat, 17 Mar 2007 11:19:19 -0000

Hi, Niraj

Why should there be a architecture department? (I am in one, and I am wondering about this)

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Mon, 19 Mar 2007 17:55:58 -0000

Hi, Oliver. I haven't heard of anyone who has gotten this to work under Linux. To other readers: A solution would be very welcome!

Re: Transparent encryption with Hibernate

Johannes Brodwall — Sun, 25 Mar 2007 17:08:22 -0000

Hi, Daniel

These tools look real cool (and simple to use). Have you considered implementing signing data in the same way?

Re: Transparent encryption with Hibernate

Johannes Brodwall — Tue, 27 Mar 2007 19:26:28 -0000

Hi, Daniel

Signatures requires a little more than asymmetric encryption, most notably, one has to consider where to store the actual signature. There's also a danger of replay-attacks if you don't include the primary key in the hash, so there are a few issues to consider to make it transparent. Nothing very impossible, though.

With regard to the different data types, have you analyzed whether encryption like this is appropriate for very short data types? It seems to me that the shorter the data type, the easier it will be to somehow brute force it. But I might have misunderstood the fundamentals of encryption here.

~Johannes

Re: Transparent encryption with Hibernate

Johannes Brodwall — Mon, 09 Apr 2007 12:19:02 -0000

Hi, Daniel

Thanks for a good introduction on how to encrypt small amounts of data. Your comment helped correct some of my confusion on the subject.

Re: Please pardon the mess

Johannes Brodwall — Sun, 15 Apr 2007 14:05:22 -0000

All right. I installed a new copy of WordPress exported from the old database into the new one and relinked everything together. It looks like it's fixed now, but I don't want to declare it healthy prematurely, as I have had two false starts before.

Thank you for your patience.

Re: The Joys and Sorrows of Exceptions

Johannes Brodwall — Sun, 22 Apr 2007 08:22:54 -0000

Good questions, Casey.

We have created subclasses of RuntimeException for SystemException and ApplicationException (should've been InvalidUsageException). Everything that is not classified is a "bug". Out top-level interceptors which log, retry etc. use this to decide the log level and retry strategy.

I don't think the categories I propose have been used as such in any open source project. However, I think one of the best things about the Spring Exceptions, is that they allow you to decide what sort of a problem it was.

DataAccessResourceFailureException tells you that the database or network is down, InvalidDataAccessUsageException tells you that the client code did something wrong, OptimisticLockFailureException is not actually an error at all (and my categories don't include it). In JDBC, these, and more, were lumped together as SQLException.

I guess what I am trying to say, is that as far as I know, the categories I propose are more a description of why I think Spring has good exceptions than it is a description of what they've done.

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Tue, 24 Apr 2007 20:13:52 -0000

Hi, Marcus

The xps_led_control is a command line program. You have to download it to a directory (e.g. c:\) and start up a cmd shell (Start -> Run: cmd). In the command shell, you enter "c:\xps_led_control -all 1", for example. Or "c:\xps_led_control -help" for more instructions.

Hope this helps.

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Thu, 26 Apr 2007 03:49:48 -0000

Thanks for the feedback Marcus. The tool is meant mostly for scripting and automatically changing the colors. If you just want the lights to be a different colors, the quickset program is your friend.

Re: Rails: The Demonstration

Johannes Brodwall — Sun, 29 Apr 2007 20:27:24 -0000

Good questions, Niraj

Rails have no problems with scalability for most usages. See RailsExpress for lots of tips on how to make it scale. My impression is that people are running Rails with 100s of hits per second without too much effort.

JRuby has just recently come to a state where it can run Rails. I would wait a little with that. Unless you absolutely MUST use a J2EE-container, I think you're better of with Apache/lighttp + Mongrel + Capistrano, anyhow.

For some cool usages of blocks, see Jamis Buck's blog, BDD from Luke Redpath, and hopefully soon, rbehave from Dan North. For the underlying justification, see Artima's interview with Matz.

Re: Spring - You've Failed Me

Johannes Brodwall — Thu, 10 May 2007 04:32:38 -0000

Hi, Per

Rod showed me the pure Java configuration about a year ago. Since we're still in the process of adopting Java 5, I have not used it yet, so I can't comment on it.

But getting teams to stop using Spring XML will be a Good Thing. And the annotation based configuration could potentially help.

Re: Please pardon the mess

Johannes Brodwall — Sat, 12 May 2007 08:31:49 -0000

For your information, I found that the problem was caused by the spam-killing WordPress plugin Bad-Behavior. Reinstalling my blog without it fixed it. It's been working for close to a month now, so I'll declare it Fixed.

Re: The coolest Eclipse plugin ever!

Johannes Brodwall — Sat, 12 May 2007 14:08:00 -0000

Hi, hong.

I don't know. If the Inspiron laptop has the lights, I don't see any reason why not. You should try it out. Let me know how it goes. :-)

Re: Spring - You've Failed Me

Johannes Brodwall — Sat, 19 May 2007 11:58:06 -0000

Hi, Christian

Thanks for the comment. I think your sentiments here are right on the money. XML (or DSLs, for that matter) is not the solution. I hope that new language features like annotations will make it easier to raise the abstraction level in Java, instead of trying to invent a new notation. For some things (e.g. @Transactional), annotations is probably the best solution, for other things, it can help make the wiring code more maintainable, but, like you say, it may not belong in the business logic.

Re: What makes a test suite good?

Johannes Brodwall — Mon, 21 May 2007 16:03:21 -0000

Hi, Anne Marie

Thanks for the comment. I agree that in principle, TDD will give us high line coverage. In practice, I have not seem a code base that gets more than 90 % or so (my own). I don't know why this always happens. In Java, it seems like checked exception is a part of the culprit, however.

However, getting a 100 % line coverage doesn't mean that you get perfect coverage in the sense of reducing the chance of a bug sneaking though.

About Universal Tests: I think they can be taken a lot further than people are doing today, and I think it will be beneficial. I am looking forward to working more on this topic. Hope to get your comments. Did you see the test cases I linked in?

Re: A Hopeful Idea: The End of Checked Exceptions?

Johannes Brodwall — Tue, 26 Jun 2007 17:06:14 -0000

Hi, Tomas

Thanks for the comment and for the kind words. I take it that you have a different experience? I understand from your blog that you also program .NET Maybe you have a good story on what kind of problems you run into that would've been avoided with checked exceptions?

Re: A Brief Adventure with Universal Repositories and REST Web Services

Johannes Brodwall — Sun, 08 Jul 2007 13:26:56 -0000

Hi, Mats

Yeah, as it turns out, Spring is a dependency hog, and the other dependencies stack up.

If you're not doing it already, you really should use Maven to build this (and other) project. It really helps with dependency mess.

Sorry about the UrlMemoryRepository. I am reworking the code, and it is in a bit of an intermediate state right now. If this is a blocker for you, I can prioritize fixing it. Let me know.

Re: A Brief Adventure with Universal Repositories and REST Web Services

Johannes Brodwall — Mon, 16 Jul 2007 20:08:23 -0000

Thanks for the good comments, Mats.

I have indeed considered using the Map interface. My main issue is how to treat keys during inserts. The Map interface is not designed for key generation purposes. I've toyed with a few options, but found none that I like.

Using URLs as keys is actually one of the neat things about REST. This will become more obvious if I get around to publishing work on more complex models.

Regarding "get" versus "retrieve". I choose "retrieve" because of the CRUD patterns (but I cowardly left "insert" as "create" to avoid the overloaded meaning of "insert"). Also, I wanted to remove the association with getters. But "get" might be a better name after all.

Re: Evil Behavior with Unchecked Checked Exceptions

Johannes Brodwall — Thu, 19 Jul 2007 18:51:58 -0000

Hi, Harald

The code as it stands doesn't work. I expect the template code was eaten by the HTML-izer of both my blog and/or crazy bob's blog. Here is the correct code:

<pre>


    public static void throwIt2(final Throwable exception) {
        class Thrower<T extends Throwable> {
            private void sneakyThrow(Throwable exception) throws T {
                throw (T)exception;
            }
        }
        new Thrower<RuntimeException>().sneakyThrow(exception);
    }

</pre>

I don't even get a compiler warning. This is a very neat trick.

Re: A Brief Adventure with Universal Repositories and REST Web Services

Johannes Brodwall — Mon, 13 Aug 2007 15:33:27 -0000

Hi, Mats

I'm thinking about GET as analogous to lazy loading proxies with Hibernate (or other persistence framework). This means that a GET request could either return a link, or the embedded object. Using the same analogy, PUT and POST requests can be similar to cascading saves, I think. This means that the onus is on the client to ensure that the correct state is transferred.

Does that make sense?

Re: When Quicker isn't Quicker

Johannes Brodwall — Thu, 16 Aug 2007 17:02:05 -0000

Now everybody wants me to code? Okay, I promise that I'll sit down some time and redo the problem in Ruby and also in Java (it's actually an interesting proposition)

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Fri, 14 Sep 2007 12:57:16 -0000

Hi fLaMeCoRe,

I see no reason why you shouldn't be able to get the lights to work from a WoW addon, and I think it sounds like a super-cool idea. However, I would recommend that you look into the official Dell LightFX SDK for this. It is no harder to use than my code, and it comes official from Dell.

Cheers,
~Johannes

Re: Lightweight Container Life Cycle

Johannes Brodwall — Sun, 16 Sep 2007 09:39:33 -0000

I've heard about Winstone from several sources now. I guess I'll have to check it out.

The diagrams are drawn using Corel Grafigo on a tablet PC. It is basically just freehand. (To be honest, my wife helped me draw it)

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Tue, 01 Jan 2008 13:04:41 -0000

Hi, Chris

Thank you for your question. This really should be a FAQ entry by now. Probably the most asked question about the tool.

xps_led_control doesn't work without the Dell drivers. It looks like you need the QuickSet tool http://support.dell.com/support/downloads/downl...

Also notice that there after my post, Dell came out with new tools for the XPS. You can find more info at http://www.dell.com/html/global/xps/lightfx/ind....

Hope this helps.

Re: CRUD, REST, DDD, Rails - these are a few of my favorite things

Johannes Brodwall — Wed, 09 Jan 2008 11:15:30 -0000

Hi, Aksel

Yes, no, I don't know. If you have a large domain model you might of course want to manage it. Any large domain that's not managed can be bad. SQL helps you some with this, but WSDL really doesn't.

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Fri, 18 Jan 2008 12:53:04 -0000

Hi, Jim

Thanks for the positive feedback. I see no reason that XPS M1210 could be controlled the same way. You probably need the QuickSet tool from Dell (http://support.dell.com/support/downloads/downl...). This lets you control the lights directly, and it also installs the drivers needed for my program.

There is actually a WinAmp plugin for XPS lights that does what you want: http://www.winamp.com/plugins/details/146182. Sadly, there is not source code available for it.

Re: Agile and contract bids

Johannes Brodwall — Mon, 18 Feb 2008 18:13:25 -0000

Hi, Aase

Thanks for your comment. I see that you've probably worked on a few happier proposals than me. It always feels like the times I've worked on offers, it has spiralled into a fear-driven hole of documentation. 90 % of what paperwork I've helped create could easily have been thrown away without hurting the final proposal. It's mostly bull* anyway. I'm happy to hear that your experience is different.

I agree that your initial velocity cannot be applied blindly to create estimates, but it's provides a better foundation than any other estimation process I've seen practiced. At any rate, my hope is to move from the mindset of estimates to that of forecasts.

My goal is to open the door and estabilish a dialogue with the customer. In my experience, no real conversation starts when nothing is developed. The paperwork only creates good breeding ground for veiled misunderstandings.

Re: Rails #1b: Heroku

Johannes Brodwall — Tue, 26 Feb 2008 20:27:09 -0000

Hi Suezanne.

Yes, you're right. I've corrected the article. Thanks for the catch.

Re: Rails intro #2: One-to-many relationships

Johannes Brodwall — Fri, 07 Mar 2008 04:22:30 -0000

Hi, Keik

I don't get the same error, and I'm wondering if you might've made a mistake in copying the code. The error message is something you get if you say

def method(@param) ...

Or

do |@param| ...

or

{ |@param| ...

Is it possible that you have an extra "(" after "find_article"?

Re: Why does so much commercial enterprise software suck?

Johannes Brodwall — Mon, 10 Mar 2008 17:12:06 -0000

Hi, Space Monkey.

We either discontinued or replaced all features not included in a web server. Briefly: EJBs we stopped using (thank god for that!); for connection pooling we first used the pool that came with Oracle, and then switched to c3p0; for failover and loadbalancing, we use our expensive switches which already has this build in; for transaction monitoring, we use Spring; we also rolled our own message service implementation (much simpler than JMS, but a drop-in replacement for our use).

This is a pretty common question, and an important one. Sadly, the answer is pretty boring. Which leads me to think that there's a lot of stuff in an application server that we really neither need nor want.

Thanks for your question.

Re: Some FitNesse tricks: Classpath and debugging

Johannes Brodwall — Sat, 22 Mar 2008 20:41:29 -0000

Hi, Ole Morten

Three reasons why I don't like solutions like the fitnesse-pom-widget:

1. You have to install fitnesse yourself. PLUS: You have to micky around with the installation. For me, maven is my only installer
2. You have to start up stuff with special commands and stuff. For me, Eclipse is my only application runner.
3. You still have to specify a path to the pom that will vary from workstation to workstation in your tests. For me, there is no changes when you relocate the workspace.

Close, but no cigar.

The debugger is nice, but the result of running the test won't be displayed in your web browser, right?

Re: Some FitNesse tricks: Classpath and debugging

Johannes Brodwall — Thu, 27 Mar 2008 22:48:22 -0000

Hei, Nils-Helge

Using plain old Fit is indeed an option that I considered, too. But now I am actually glad I didn't. I hope you'll like to try out the code from this article.

FitNesse is definitely not designed with embedding and extending in mind. But when I was willing to dive into it, I found it wasn't that bad. I really wish my "trick" with writing my own main class was closer to the intended use, though.

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Fri, 18 Apr 2008 11:56:59 -0000

Hi, Patrick

I expect that Dell has a different driver for the XPS 720. As I don't have access to an XPS 720 it is not possible for me to fix this. If you're familiar with C code, you can twiddle around the indices in the buffer and see what happens. If you can find out how to work it, I'll include your modifications in my source code (if we can make a version that works with both the laptop and desktop).

Also, you could look into the Dell official Light FX program, which is roughly equivalent to mine. See http://www.dell.com/html/global/xps/lightfx/ind...

Regarding color choice - this is sadly not possible. My program exposes the full range supported by the XPS laptop at least.

Re: Dell XPS Vanity Lights Blink!

Johannes Brodwall — Mon, 21 Apr 2008 18:16:39 -0000

HI, Sean

The program is a command line program, double clicking will produce exactly the message you see. Please execute the command on the command. If you don't know how to do this, you can try out Daniel's description in these comments.

Re: Four bold claims about SOA

Johannes Brodwall — Fri, 02 May 2008 14:24:38 -0000

Geir Hedemark points out another thing that I didn't really think of about BPM: If you expose and reuse your services (Use Case steps, remember?), you can no longer change these. So your "flexible" processes may be composed of "frozen" steps.

Re: Four bold claims about SOA

Johannes Brodwall — Mon, 05 May 2008 07:31:59 -0000

Hi, Geir

Do you mean ESBs or BPM? I thought BPM was what people used to deal with events?

Personally, I've never found a conflict between object orientation and event driven applications. I would love to hear a bit of elaboration on this.

Re: Four bold claims about SOA

Johannes Brodwall — Wed, 07 May 2008 05:20:55 -0000

Both Geir and Lars Arne seems to have more insight into the use of ESBs than me.

Personally, I have never seem the problem that Geir is describing with using OO in an event driven world. Granted, I have never perceived this to be a major source of problems, but I end up translating events (usually incoming documents) to "command objects" which update the state of the object model. I've never missed an ESB when doing this. What am I misunderstanding?

Lars Arne's "galvanic divider" is closer to things I have encountered. But in my cases the "galvanic divider" became just another layer of crud on top of many more layers of crud. As I understand it, this view of ESBs would either mean that you have to have a generic representation of any message type or you need to have individual representations for different messages. If you go for the first option, you're screwed, as most people who've tried know. If you go for the second option, don't you just add another layer of complexity with no corresponding value, as the new representation will have to match the old one, anyway?

Maybe it would be clearer to me if I saw the ESB tool you guys use.

Re: Enjoyable development

Johannes Brodwall — Wed, 14 May 2008 15:14:00 -0000

Flow is definitively an important component of happiness.

"If all my tests took less than a second"? Do you mean more than a second?

Most of the tests I write first are independent of infrastructure, which means that they run really fast. I try to separate out my slow-running tests (e.g. test that a search generates SQL that retrieves the correct result from the database). I haven't doing any soft of formal categorization here, though.

I find that either I run a single test in the IDE. Then it should run fast. Or I run all my tests for the command line. Then everything should be run. So I don't need to categorize stuff now.

Re: Enjoyable development

Johannes Brodwall — Thu, 15 May 2008 04:35:25 -0000

Hi, Geir

Thanks for a very interesting question. I think I might want to expand this into a full entry eventually.

I think the risk of my tests running this quickly are fairly slim. But if it did happen, I would still want to separate out the functional tests that we create in cooperation with domain experts and the system level tests that simulate realistic operating conditions. I'm happy with the system level tests we have now, which stress the system. There's no way these could run in under 1 second.

But neither of these types tests are JUnit tests. Our functional tests are implemented in FitNesse and our system tests are scripts that push data on the system (for a web based system, I would consider JMeter).

For tests implemented with JUnit, I would not see any usefulness in the distinction if things ran sufficiently fast. I might consider deleting tests that were covered sufficiently by the functional tests, but since these are run by different tools, it might be hard to find out exactly what tests could be deleted.

I would keep my CI server, though, so I was sure that changes by every member of the team (myself included!) actually passed the test suite. I might even add a failure condition if the tests ran for too long, to make sure that we didn't start down the slippery slope of slow tests.

Re: Enjoyable development

Johannes Brodwall — Thu, 15 May 2008 19:53:27 -0000

If everyone (including the questionable professionals who currently don't really test!) ran continuous testing in their IDE, I wouldn't feel the need to run these tests in CI. But we use our CI server also to build the software and push it out to test servers for performance testing. So I don't know what the point of disabling the tests would be. :-)

I think functional tests will tend to vary a lot from project to project. It really depends on what your interface to the outside world is.

A minute to start up Hibernate (Spring is seldom to blame) is unacceptable for a functional test. In my functional tests, I have replaced the whole persistence layer with a stupid in-memory replacement.

Re: Forskning på smidige prosjekter

Johannes Brodwall — Mon, 26 May 2008 16:05:02 -0000

Hei, Magne

Jeg har merket selv at det er veldig lett å falle i felle med å forsøke å avvise kritikk ("deflect") i stedet for å svare på den. Jeg forsøker selv å ta meg i nakkeskinnet mer her.

Forstår jeg deg riktig når du sier at et studie for å finne ut av effekten av smidige metoder (eller feedback) burde hatt en dimensjon til? Slik at spørsmålet blir "innen hvilke problemtype er hvilken iterasjonslengde korrelert med vellykkede prosjekter?"

Jeg skjønner poenget ditt med begge spørsmålene som du spurte på Geilo til å være at noen problemer går det ikke an å ha meningsfull fremdrift innenfor en tidsperiode som er for kort. Er det riktig? For å bruke en utslitt metafor: Det er ikke meningsfullt å ha iterasjonslengde på under 9 måneder på leveranse av spedbarn.

Min erfaring er at de fleste oppgavene innen utvikling kan og bør stykkes opp i oppgaver på under et dagsverk. Når jeg ikke gjør det selv, produserer jeg dårligere resultater (og jeg finner alltid i etterkant at det var en måte jeg kunne stykket det opp bedre). Og det er en ganske stor gruppe med selv-erklærte "dyktige" utviklere som ikke klarer å stabilisere koden sin i løpet av en dag.

Kanskje et annet område som kunne være verdt å få bedre empiri på.

Som du påpeker er det motsetning mellom feedbackfrekvens og størrelse på chunks. Jeg tror den viktigste faktoren her ikke er problemtype, men prosjektstørrelse. Men smidige prosjekter oppfordrer typisk til mindre prosjekter. Jeg tror dette både er for å underbygge hyppig feedback, men også fordi det er en vanlig oppfatning at store prosjekter er mindre vellykket. Som igjen går tilbake til det du sier om planer som er vanskelige å sammenstille.

Et spørsmål til sist: Jeg forstår deg til å si at det er bedre å forske på "NÅR fungerer X bedre enn Y", heller enn "FUNGERER X bedre enn Y". Det kan jeg si meg enig i. Men dette endrer ikke problemet du påpeker med at vi ikke klarer å definere "BEDRE", ikke sant?

Re: Forskning på smidige prosjekter

Johannes Brodwall — Mon, 26 May 2008 16:17:07 -0000

Hei, Magne

Ettersom "vi smidige" ofte er veldig dypt nede i enkeltprosjekter er det definitivt en kjempefare for å overgeneralisere.

Det praktiske motstykket til det du sier er at vi observerer "dette ser ut til å fungere for oss, jeg vet ikke om det vil fungere for dere". Jeg bestreber meg veldig på å presisere på at jeg har veldig få datapunkter, men det er lett å la seg rive med.

Takk for en spennende diskusjon.

Re: Three challenges for agile projects

Johannes Brodwall — Tue, 10 Jun 2008 06:15:27 -0000

Hi, Jerome

Thanks for the comment.

You are indeed right that my context is greenfield projects or at least projects that have a long projected cost before any revenue. A more constant revenue flow can possibly be much more aggressive.

My experience is that even projects with frequent iterations often fail to actually deliver those releases. If you don't experience the same, I'm very happy for you. :-)

My project currently demos and simulates production once every two weeks, but we notice that larger projects often need more time to come together, so the "once per month" goal is a tolerant one.

I've added AgileInAction to my blog roll. Very interesting post (although I am not sure I see the immediate relevance).

Re: Three challenges for agile projects

Johannes Brodwall — Tue, 10 Jun 2008 18:31:11 -0000

Hi, Jerome

More great insights!

We have also automated our testing and release process and this helps a lot. But sometimes we run in to minor or major snags along the way. For example: We can have failed to stabilize the code after a bug was discovered in a late automated test. Or maven-release-plugin can act up.

And our PO doesn't want to meet all that often. Or at least that has been what we thought. We do suffer from unfocused iterations, though, and your point of one-week iterations been more focused could apply to us as well.

The main point of my 10 % of business case is that the first delivery of a system often is at the 50 % or higher point. At this point, there's little opportunity to exercise control. Indeed, many of the people I talk to still pursue projects with a delivery date a year or more into the future with a single release. I have had some luck with waking people up when I talk about 10 % of business case, as the rationale for this is so obvious from the goal itself.

As you point out: The first release is the hardest.

But if we could release even more frequent with the certainty of good enough quality that the customer wants, that would be even better.

Re: The Myth of the Silo

Johannes Brodwall — Mon, 16 Jun 2008 17:32:29 -0000

I don't think of the layered system that I'm talking about as a silo. Rather, I think of it as a business level service composed of several component services. What characterizes such system is a great deal of fragmented responsibility.

The people responsible for a single layer generally seem to consider themselves service providers for the layers above.

This is not a agile way of creating software. But it's a common implementation of medium-grained SOA services.

Thanks for the kind words, Eivind. Your closing remark is exactly what I wanted to express.

Re: Fire påstander om SOA

Johannes Brodwall — Sun, 22 Jun 2008 15:38:25 -0000

Hei, Lars Arne

Takk for gode kommentarer.

Jeg tror vi er enige om at det er en utfordring å skulle bygge "systemer av systemer", slik du beskriver. Jeg tror imidlertid at dette er en arkitekturmessig innfallsvinkel som ofte er feil.

For det første er ikke gevinstene av gjenbruk så store som folk forventer. For det andre er kostnaden ved å bygge distribuerte systemer mye høyere enn folk forventer.

Men dette har jeg tenkt å skrive mer om i fremtiden. :-)

Når det gjelder "å få integrasjon ut av applikasjonen" er dette også noe som må gjøres med forsiktighet. Jeg har sett mange middleware løsninger som får integrasjonen ut av løsningen, men på den bekostningen at man i stedet må foreta en kostbar integrasjon med middlewareplattformen. Ooops!

Re: Teaching good software design

Johannes Brodwall — Tue, 24 Jun 2008 12:11:30 -0000

Hi, Eivind

Thanks for another insightful comment. As you say: We shouldn't stop doing object-orientation. My experience is that I should only stop recommending that others choose object-oriented solutions when asked for my input.

Trying to force people to use object-orientation (or testing for that matter) without proper understanding is probably not a good idea. With teaching tests, at least I know what to point to as good examples that won't lead people astray. With OO... not so much.

Re: [link] Package by feature

Johannes Brodwall — Tue, 29 Jul 2008 18:02:44 -0000

Thanks for the comments.

I suggested this structure for a project some time back, but a few others insisted that it was "too weird". John O'Hanly has made a web framework called Web4j that he claims uses this structure. It might have some more clues.

Domain classes that are used in multiple features: Most examples I think of the classes have one main feature. For example, "product" would probably be used by "order", but belongs in product. Do you have an example of a domain class that would be hard to place?

Re: [link] Package by feature

Johannes Brodwall — Wed, 30 Jul 2008 07:53:53 -0000

Thanks to Marcus and Espen for valuable experiences of trying this kind of approach.

I think the most valuable point is that being dogmatic either way (like the original article) is a bad thing. Like Thomas says: "There are no 'best practices', only good ones".

But I find Espen's comment about not having enough information to create the structure in an agile project to be puzzling. I find I can organize user stories in rough features. Isn't this sufficient?

Does anyone else have experience on finding feature categories for your code?

Re: Fire påstander om SOA

Johannes Brodwall — Tue, 12 Aug 2008 18:08:08 -0000

Hei, Rolf

Jeg er enig med deg i at noen av påstandene i artikkelen min kan virke som stråmenn. Men jeg har fortsatt til gode å få noen til å komme med en konkret påstand om "hvorfor SOA" som jeg kan forstå som noe annet enn en av disse fire.

Din holdning til at det hele dreier seg om forenklet infrastruktur virker pragmatisk. Betyr dette at du grunnleggende sett sier at "SOA = SOAP + en del andre passende teknologier"?

Dette er det mange SOA-evangelister som er uenige i.

Jeg er selv uenig i at SOAP + venner har tilbudt en pragmatisk teknologistack. Jeg ønsker ikke å "hoppe bukk" over disse standardene, men i stedet stanse før dem: Ved HTTP og XML.