pmd/blog

And the winner is...

WidgetFX is a nice project, but it's young and users will not use a widget engine with a minimal set of widgets. A great way to solve such a problem is a contest. A contest gets the buzz going, creates content and makes people involved.

WidgetFX 1.2 was released in the end of June and at the same time the first WidgetFX contest was announced. Having previously developed a widget and grown quite fond of JavaFX I gave it a try. After all, I already had an itch to scratch. Besides writing the code and blogging about it could enter me into two contests at the same time. Well, turned out that it did take a bit longer to finish a usable version of the ImageEditor in ScreenshotFX and in hindsight I was only at most half way there when I wrote that blog post. Anyway, I had time to finish a version it has even been useful for me a couple of times already.

The contest had slipped my mind since I've been very busy for the last few weeks. Imagine my surprise when I came home tonight and saw an email from Stephen Chin with the subject "Congratulations on Winning the WidgetFX Contest!". Really? Now that's simply awesome! :)

Now when I won and all I feel a bit bad that I've not written a single line of code for the project in weeks. After all... there are a lot of things to improve... ui... exporting... not to mention submitting the ImageEditor to JFXtras :)

Well, that's a lot of words when all I actually wanted to say was Thank You to the people who liked my widget enough to deem it a worthy winner!

See you in the next contest :)

On to the next widget

JavaFX 1.2 was released a while back with quite a lot of new features. The release was also accompanied by a blogging competition to get the buzz going. I didn't think I had anything to enter into that contest since I've not had much time for JavaFX. However, a couple of days ago new 1.2 compatible version of WidgetFX was released and I thought it was time to create a new widget. As I've said before, creating a widget is a fun way to explore JavaFX and right now it actually seems like I could enter a blog post in time as well :)

Anyway, on to the code...

With the increased performance now even more than before I find JavaFX to be a great way to play around with and create quite advanced stuff in a very short time... while on the other hand the other way around might be true every now and then as well.

The project

For example... a college usually attaches screenshots to mails when he want's to describe some change or feature update to the company site/admin interface. Obviously that makes it easier to quickly grasp what he's talking about. Another college mentionend that he probably has Photoshop running all the time. Well, that might be the case, but I doubt Photoshop's memory requirements allow for that. That made me think that a quick to access widget really should be the way to go for these things. It's only going to take a screenshot, how hard can it be?

Getting a screenshot

The power of JavaFX beeing built on the Java platform comes to play here... I quickly used the Robot class to get a screenshot of the desktop. The point to make here of course is that I had used this class a few years ago and even though JavaFX doesn't have a screen capturing feature I could use my previous Java knowledge for this.

        Robot robot = new Robot();
        BufferedImage bi = robot.createScreenCapture(new Rectangle(x, y, width, height));

Very easy... a few minutes of work with some file handling and other stuff. But hey, just taking a screenshot still means that one has to manipulate the image in another program to highlight something. I did remember that I saw a JavaFX drawing example on the JavaFX.com site. That's probably easy to add. Sure enough, following Jasper Potts' example code gave me a Node I could draw on in no time at all.

Capture screenshot & draw

Such a feature would of course be useless unless I could save the edited image. I did remember that I previously had seen something like that among the tutorials as well. After a while I found this demo with the save image feature.

Something unsupported

A few lines of code, unfortunately hacking JavaFX a bit to get it to work. Usually not a good idea, but I can't go without a save feature. Turned out the "save node as image" function didn't work any longer, probably broke in the JavaFX 1.2 release. Here's one of the bad parts beeing such a young language and all. When working with JavaFX there's been quite a few times when things like this has happened. Features like layout, controls etc. which one would think obvious parts of such a language/platform have been missing. Fortunately for my little program this exact example also shows the strenght of JavaFX in another way. I'm not talking about the language here, but what it's build on. I.e the Java platform and it's community. Someone had already solved this problem in Sun's forum. I certainly believe those things to be what will make it survive and prosper.

Of course, I'll have to maintain this code since it'll most likely break in every release, but I quickly got the feature and eventually I can replace it with a library. Perhaps the feature itself will be added to JavaFX some day.

Dragging around

Hover over the square to see what you can drag

Great. Capturing a screenshot, drawing stuff on it and saving it... done? Hmm... it really would be fun to be able to mark an area and darken the rest of the image. Would certainly look better in many cases... I've used Path before and it seemed to be suitable for this task. It did take some time and it's pretty basic, but after a couple of hours I had something useful.

This is made all by me so for this code I don't have anywhere to link. Here are the three files for Example2: Example2.fx, MovablePath.fx and Point.fx

Finishing up

I got a couple more features that would be fun to make, but it's probably a good time to put together something usable at this point. I will have to put some time into the GUI as well. Can't wait for the tool Tor demoed at JavaOne 2009 (it's part of James Gosling's toy show). Looks awesome!

That brings me to my final point. I've found that the way I like to develop in JavaFX is to always create new Stages (and sometimes whole projects) for everything. Just like all programming it's a good thing to keep classes and methods small, but with NetBeans an added benefit is to be able to preview a Stage. Jumping around in a lot of classes takes one away from that preview. When I think about it it would be nice to have an option to lock the preview to a certain class or perhaps the project main class. Anyway, when I'm done with one of these Stage-tests I "convert" it into a real class which usually mean that I'll have to remove a lot of test code, commented code and other useless lines. Then it's ready to be put to work in the real project.

Conclusion

Is short I'm having fun with JavaFX and with version 1.2 I've not felt any slowness at all. I'm still missing things, but progress is made. It would be great if the next version could be binary compatible though :)

Interview with Simon Phipps about Open Source

Today I was catching up with a bunch of FLOSS Weekly podcast episodes. One episode really cought my attention, the FLOSS Weekly 39: Simon Phipps episode. Simon Phipps is the chief open source officer of Sun Microsystems and talks about open source in general, having a business strategy based on open source and how Sun has come to be the company it is today in regard of open source. It's an amazing interview!

Have you ever been in a discussion with someone about Open Source and the reason either for it to exist or for a company do adopt it? I have, and I always struggle with the explanation. I usually find it difficult to give a conclusive explanation of the business value of open source. Usually I get the feeling that the person I'm failing to convince just get's reinforced in his or hers opposite beliefs. I'm always annoyed by that since I know that open source is a good thing and for that reason I tend to stay away from trying to convince people.

I think listening to this interview can answer all of those questions with an intelligent diskussion. I will listen to it several more times for sure!

More people must have found it good since in the following FLOSS Weekly episode 40 the hosts Randal Schwartz and Leo Laporte talked about the positive feedback and how Simon Phipps appearently had got so much into the discussion that he now was thinking about writing a book. I would pre-order that book today!

I just feel good right now, I love hearing really smart people talking about great things like this :)

Tapestry 5 and GWT - part 2.5

The source code

I should have done this a long time ago, but here we go. The code for the Tapestry 5 and GWT tutorial part 1 and part 2:
Download NetBeans project

The following versions of GWT and Tapestry5 are used as well as their respective dependencies that can be found on their sites.

GWT 1.4.60 - http://code.google.com/webtoolkit
Tapestry 5.0.15 - http://tapestry.apache.org/tapestry5

JavaFX, WidgetFX and my first widget

I became interested in the early version of the JavaFX Script language, F3 script, thanks to the nice GUI and graphics demos. I'm guessing I'm not alone in that :)

Anyway, the preview release of the JavaFX SDK was released a while ago and I looked at it with some interest. I became more interested in actually doing something with it when I saw the WidgetFX project, simply becuase I like the idea of widgets/gadgets etc. Until now I haven't been able to develop and run them in a Java environment. I also saw the oppertunity to actually learn JavaFX Script since widgets are a really good way to make a really small, but still useful application, while getting to know the language.

If you're interested in developing widgets you really should check out the WidgetFX Developers Google group. People like Stephen Chin, who's been answering loads of my questions :), are really good at answering all kinds of questions about WidgetFX!

It took me quite a lot of time to get at least a bit used to declarative UIs. I'm still not there, but I've made some progress and it's fun.

This is just a small post about my first widget, a disk space monitor. It's not a step by step tutorial, more of a tips and tricks for a beginner. I've included stuff I've learned when working with the JavaFX Script language and the WidgetFX API. It'll require at least some basic knowledge of the JavaFX script language.

Read on, visit the quite sparse DiskSpace Widget page or try it out right now.

Ubuntu diskspace on /

I've had very little space left on the root drive for quite some time now, but I've not come around to check into the problem. After a crash today I was left with 1mb and therefore was forced to deal with this ;)

As it turned out the problem was much easier to solve than I had lead myself to believe. Not beeing very familiar with Linux that is. A quick googling gave me the following blog post from Arun. Just doing a simple du -hc –max-depth=1 gave me the directory occupying my missing space.

Sometimes things really are a lot more simple than you think...

Taking the first steps with MicroEmulator

I started looking at MicroEmulator a few days ago. Unfortunately, when I tried to start MicroEmulator from the command line locally it refused to take a jad file (or class) as argument. Starting the emulator and dragging a jad file into it worked as it should. But running with an argument froze it at startup.

Fortunately, the solution/workaround wasn't difficult...

Forwarding IIS to Tomcat

Every now and then I get the chance to do something Java related at work. This week it was installing Tomcat 6 and forwarding certain urls from IIS to it.

It really shouldn't have to be too much of a problem, but of course I knew that IIS wouldn't play ball. It took a couple of hours with the help of a college, but finally it worked!

Testing a web service

During the last two weeks I've been busy building a web service at work. It's the first web service for the company I work at as well as the first web service I've ever built so it's been fun to learn a couple of new things.

The work flow consists of a couple of steps, one of them being a connection to another service performing a payment of a credit card if it's a credit card order. I wanted to be sure that it could sustain a fair load and went googling for that kind of tool.

I found soapUI and it's great! It took a couple of hours, but after that I had a call to the web service up and running. A test that asserted a valid soap response as well as a XPath expression that counted the number of messages returned and checked them for correct return codes. Also a load test running tests for both invoice and credit card payments. Really powerful and cool I must say.

Not only that, it also got a good documentation which makes setting up a project really smooth. I will definitely recommend that we buy the Pro version for the next web service project!

Tomcat 6 Windows service

I installed Tomcat 6 at work the other day. The server is a windows server running our software. Most of the developers don't have admin access to it.

I installed tomcat as a service and choose to have it running at startup. It didn't take long before one of my fellow developers without admin access logged in and got this error message.

Very strange. He had full access to the Tomcat directory and tomcat6w.exe, the Tomcat monitor process that was giving him the error dialog. A colleague (thanks Oscar) pointed out that tomcat6w.exe probably was trying to contact the service. Of course! Since tomcat6w was running with the logged in user's privileges and the tomcat service was running as System the monitor program didn't have enough access.

Suggestion: don't install (I don't actually think I did that, so it might be automatic) the monitor program for people without access to the service.