Sunday, October 21, 2007

Sunday at OOPSLA '07

We're getting close to the end of the real day here at OOPSLA '07. I've worked today as a flotter from 7h to 10h and then again from the 12h to 16h (I did 1 extra work hour than I was scheduled for to help people). Now, you must be wondering what a flotter does, right? Very simple: flotters float! Meaning we just stay in the Student Volunteers (S.V.) Room (a nice room with great wifi, power and free food) and wait for some work to show up. This could be anything: from replacing a missing SV to carrying stuff around and helping in registration. But most of the time, you just sit in the SV Room and chat, organize extra activities (such as Ice skating on Monday or Tuesday!) and have fun. This is how I managed to write the whole last post, read my feeds, check emails, etc...

I'm now off duties but I've already lost around 65% of any tutorials and around 80% of any workshop for today so I decided to stay here and write a bit about the conference itself. We got a lot of people here from all over the world. I've met Canadians, Polish, Americans, Mexican, German, Romenian and even Brazilian students. :) I'm not sure what we're doing tonight but Mariana promissed she would report on the tutorial she attended: "Pick up your pen!" from Steve Metsker. I will try to upload, classify and comment every picture we got from yesterday and today.

Tomorrow afternoon I will be hosting the tutorial: "Why users say 'Start with the Screen!': Effective Test-Driven Development, Presentation Layer-First" from Bobby Norton and Chris Stevenson and I will report about it. I'm not sure yet about which tutorial or workshop I will attend during the morning but I'm seriously thinking about Steven Fraser, Dennis Mancl and Bill Opdyke's "No silver bullet - a Retrospective on the Essence and Accidents of Software Engineering" although I might attend to the beginning of the Mini-PLoP which would not be as good since I would have leave in the middle. I don't know. I will probably talk to Linda Rising about it (since she's responsible for the PLoP) and find about it tomorrow morning during breakfast.

So, activities here finish around 17h (which is in a couple mins) and then we will probably try to agenda something with other SVs and go out in the city and later on go to some pub maybe. Tomorrow's duties start later on (8:30h instead of 7h today) so we might have a couple more sleep hours (or writing). And, finally if anyone is wondering where will be next OOPSLA: Nashville, Tennessee. So get ready to subscribe as student volunteers because there are around 10 or 12 guys from Monterey University which means, there are not limits for a single university. You just need to show interest and be ready to work a little to get a lot of fun.

That's it for now guys, I'll get ready to go somewhere with Mariana before we meet with the rest of the SVs. Bye bye and see you guys later.

From Montreal after the first workday

Hello there,
I'm writting very early in the morning while Mariana takes her bath. It is sunday morning and the OOPSLA conference starts today. We've been in Montreal for 2 days already and the city is very friendly. Distances between things are quite big although it is not even nearly as crowded as Sao Paulo. Friday we walked a lot and saw the UQAM university and a very nice park filled with squirells. We spent the evening with our hosts chatting, eating and drinking. They cooked a very nice "Fondue chinoise" which has nothing from China from what they told us and we gave them their gifts. Yesterday (Saturday) they took us for a car ride in the city where we could see the Formula 1 circuit and quite some parts of the city.
In the afternoon, we had a very good vietnamese sandwich in the best vietnamese sandwich maker in town according to Vincent. And then, from 15h to 19h, we started our work at OOPSLA at the registration booth with Eduardo, a Brazilian that lives in Waterloo (since 1999), Diana, a local girl that studies at Mcgill university and Bernardo (I guess), a Mexican PhD student. It was pretty cool since there were not so many registration but we could register Dick Gabriel, Linda Rising and Martin Fowler. Dick took some very embarrasing photos of Mariana while she was eating our excelent vietnamese sandwich. I will have to ask for them later. :)
We left after that with a couple of Mexican students from Monterey University (Juan and Ramiro) and other Brazilians (friends of Eduardo, also known as Dudu) and a polish PhD student from Waterloo called Mihau (don't know if this is correctly spelled). We went to a nice classical bar called Saint Sulpice which is in Rue Saint-Denis. That's an amazing thing about the city, all bars areas are close to the biggest unversity. Rue Saint-Denis is close to UQAM (Université de Québec À Montréal) and there are other streets filled with bars close to the McGill university and another close to Columbia.
We left the bar around 23:30 and went to sleep just arriving at home. I'll continue for today later on. This is only for now but I'll update more later.

Bye bye

Monday, October 15, 2007

Quick news before the trip

Some very few news before the trip:

I will be arriving in Montreal the 19th, which means, 1 day before any activity from the OOPSLA. I'll be staying at a friend's house (which is great!) and the first two days I'll probably walk a lot around the city. I'll try to get some nice picture and upload them. From the 21th to the 25th, I'll be full time at the conference but I'll try to post (with the help of Mariana, my girlfriend) some reports about the conference, talks and chats we will have. This will only happen during the nights because we won't have any laptops in site.

We leave Montreal on Saturday 27th by night by bus to NYC. We should get there by 7am or 8am of Sunday 28th. We'll enjoy the day walking around the city and then get to a friend of a friend's house where we will be staying for the news. Our only plans will be to visit the museums and walk a lot. I'll try to post some pictures too.

If you have suggestions, please send them in.
Write back soon (hopefully).

Wednesday, October 10, 2007

News after almost 2 months

It is quite evident that I'm not a compulsive writter. Almost 2 months since my last post now but I've got some pretty good amount of news.

First and sad news: The paper was reject by the ETX comittee. The following reasons were the principal ones that got it rejected:
  • It was not clear enough in the sense that the english writting was not very good.
  • The paper had to focus mainly on either the project history and then be a paper about a success case of using Eclipse's RCP or on the technical side. This last one should bring to discussions the main CAD architecutres and discuss the impact eRCP could have on it.
  • The last reviewer said that the project and the article were pretty good but it lacked an implementation to prove itself usefull. I don't know if I didn't understood the comments or if the reviewer really (REALLY) didn't understand what we wrote.
So, as they say, better luck next time right? We will work more to get it accepted for next year's OOPSLA.

Other than that: Archimedes is currently almost completetly stalled. I haven't been finding time to code anything on the project with the master's work. It is sad to admit but I should only be able to refocus on the project in december or beginning of the next year. I surely hope next year I will have again another group of volunteers to work on the project on the XP course.

More personal matters and things that might interest this blog's readers. I will attend (with Mariana) at the OOPSLA '07 anyway. We were accepted as student volunteers so we will spend our whole week (from the 20th to the 25th) helping the people from the organization to make this amazing conference. I cannot promise much but I can assure everyone that me and Mariana are going to do our best to post everything we can on this blog about the OOPSLA. Maybe we even broadcast a couple talks if we manage to (and are allowed to). Once we find out what will be the infrastructure there, we will try to keep you guys up to date.
We leave São Paulo the 18th evening and reach Montreal the 19th morning. Works might start the 20th and we will stay in Montreal until the 27th (or 28th) depending on some details.

Last, but not least, I've classified with my team (Jeferson R. da Silva and Marcio Oshiro) to participate in the brazilian's finals ( in portuguese) for the ACM ICPC programming maraton contest ( So I will be in Belo Horizonte from the 9th november to the 11th. We surely hope to manage to be in the top 10 this year and we are training a lot for it (which is the reason why Archimedes lost my coding time).

Well, that's about it. And remember, from the 20th to the 25th, stay tunned because news will be flowing quickly here. See you guys.

Monday, August 13, 2007

The article at last!

Just to change a bit (and follow Danilo's advice), I've been really busy but I've submitted the article at last.
The last weekend has been quite insane. Sleeping around 2 or 3 hours per night and working the rest of them on this article for the Eclipse Technology eXchange conference to take place at the OOPSLA 2007. The last result was not the best thing ever produced but I am quite happy about it.
Even if it is not accepted, the parallel developed with IDEs and CADs looks promising. Even more since I've read this article ( where programming environments (IDEs) and CADs/CAMs are joined together in a design software category. Maybe with this kind of support, I can have stronger arguments further on to support my theory that CADs should have a platform to be built on, just like Eclipse is a platform to build IDEs.
I'm sorry since revisions won't help to submit the article since it is gone already but I'm sure Mariana and Alfredo (my co-authors) would be glad if the article was improved only for its own good. For those interested, the article is published at and you can send me comments, critics and suggestions to my email, through here or any other way you can find.

With the article madness I haven't been able to do anything else so today I've taken my agenda and solved a couple things. Messages about Archimedes at the sourceforge form have been answered at last, emails are almost all solved but I still have to read about 20 articles and hear some 10 podcasts besides the university works that still need to be done. So don't expect many updates here in the next few days.

Changing of subject abruptly: this morning, while coming back from my run (to keep my not-so-round shape), I got this crazy idea. Since Ohloh is being such a success, I was thinking about a trip network just like the Lions club has but for FOSS developers to attend to FOSS conferences all over the world with reduced costs.
The idea is that most FOSS developers really love what they do and would certain attend to every single event where they can meet their idols developers or just their friends. Problem is that this costs more than a lot can afford: plane tickets, hotels, meals, conference entrance, etc...
On the other hand, when there is a FOSS event somewhere in the world, there ought to be more than a couple FOSS developers living in that place. Being so, some of them might be able to host a developer for the conference period. The campaign "Host a FOSS developer" can even be spreaded to FOSS friends or even FOSS grandmothers.
In return of being hosted, the FOSS developer could repay the hosting with commits to some project the hoster points. This way both sides benefit and even get to understand each other's world a bit better. If I get to ellaborate this idea a bit better, I will try to contact Ohloh's guys and maybe organize this. I'm sure some well known developers would love to contribute to such an initiative.

Just to finish this post, the WSL article accepted at the FISL 2007 is already translated. I just need Mariana to revise it because my english is a real crap. As soon as it is decent, I will publish it somewhere and post the link here.

Once I get more info to talk about, I will post again. Let's hope it's not too far from now.

Monday, July 30, 2007

Late as always

As usual I am very late with everything. But this time, things are a bit more dangerous. I haven't finished the article about archimedes to submit to the Eclipse Technology eXchange (ETX). Worse than that, I am quite stuck with it. Can't write more than 1 paragraph per day currently. A big problem.

Also, I stopped working on last thursday so I should be a bit more active and present from now on. Got a lot of things to do but still I will make an effort to keep this up to date.

I have very few news at the moment about anything. Just a couple things that might interest people from around here:
I've been going to a Coding Dojo that just started in São Paulo ( It is a very nice practice that aims to make programmer train their talent just like musicians and sportists do. Our meetings have been very nice and it is helping most of us to learn python and also to be more disciplined. We just changed our schedule to have meetings weekly on wednesday at 20:00 local time.

Also, I just became a student sponsored by the Qualipso project. I will be doing my masters on the lines of the project and, therefore, hope to finish my studies providing a nice set of practices based on agile methods to develop open source software. And, if possible, I hope I will participate in some nice open source development on the next couple years.

Last, but not least, I just joined as a junior member a very nice group called Agilcoop. The groups main purpose is to spread agile methods into the industry to improve the quality of software produced. Got a few nice tasks to do such as learning some Java FX (that's why I've been having codeaches with the eclipse plugin) and learning to write some classes. It promisses to give me work and fun.

Well, I guess this is all I can get you guys now. I hope to write more often from now on but let's see right?


Thursday, July 12, 2007

Selection service, archimedes and docs

Once again I am too late to keep my old pace. Anyway, the end of the semester is always very time consuming.

Anyway, I would like to comment on a few things about RCP today.
I learned a few stuff about it lately. First thing is that there is a very nice tutorial about it at The other thing is that this selection service can be quite useful if you start working with it from scratch.

Archimedes didn't, until now, had anything to do with that service and refactoring it to use the service will be another big work. With this, there are now 5 tasks that have top importance:
  1. Remodel the intersection finder system
  2. Re implement persistence support with XML/Arc, images, pdf and svg.
  3. Refactor Archimedes to make it profit from RCP's selection service.
  4. Adapt Archimedes and its plugins to be built with maven.
  5. Improve Developer support and User support.
I listed those without a priority order but I am sure those are top level.

I should be getting more time to write here and to code during the next semester since I am quitting my job to dedicate to my masters.

The development speed, however, will probably not improve a lot since I am now almost on my own to code. I might get some help from one or two volunteers but it won't be enough to keep the pace from last semester.

Apart from that, regarding documentation. I finished translating an article I wrote with Mariana last semester for the FISL. She needs to read it and correct all my numerous mistakes but the big boring part (translating) is done.
In the same subject, we are preparing another article in English to present Archimedes at the Eclipse Technology eXchange that will be held at the OOPSLA 2007 in October at Montreal. Once we finished it, I will release it somewhere on the net and post the link. If I can, I will try to do it one week before the submission date so that I can hear critics.

Basically that is it. I wish I would write here more often since I probably don't post all I could and would like to. But, hey, it's life right? So seen you soon (hopefully).

Monday, June 25, 2007

ToolBar paths and Archimedes news

The end of the semester is always a disaster. Tons of things to do and not enough time.
For once I don't have tons of tests, the only hard work is to maintain the job, the work on Archimedes, the studies and the corrections going.

Anyway, enough complaining.
I got some news about Archimedes:
This release is coming to an end but I am proud to say that most of the work that should have been done is complete. There are a few details missing but those are mostly related to difficulties we are finding with RCP.
Both the import and the export feature that will become the save and open one are finished, all that is left to do is to integrate this with the platform so that the users can enjoy all the flexibility of Eclipse's wizards.

Also, Mariana is now responsible for releasing updates for the old 0.17.x version and get our bug fixes and new features ported to that platform until the RCP one is not perfect. I wish her luck and hope to see a lot of report from you guys when she does.

Most of the reported bugs have been correct so far and I even learned how to organize the action icons on the toolbar. This means that, from now on, Archimedes' toolbar will be a bit more organized than it was before.

Since I found absolutely NO documentation about this, I wanted to write a little bit about how to make it work. It is quite simple but worth saying.

Mainly, when you extend org.eclipse.ui.actionSet and create an action, you can add two attributes: menubarPath and toolbarPath. The first one is quite decently documented so you can find several tutorial that will explain you that you should add some MenuManagers in your ApplicationActionBarAdvisor and then refer to the paths you set on those managers to decide where the actions should appear.

Regarding the latter, you will find almost nothing. I've search a lot and very little is published to explain you one very tiny and simple thing: It works EXACTLY the same way. May sound stupid for me to say it like that but if you have no documentation or example, this may not be evident because when you create ToolBarManagers, you cannot add slots within those to specify boxes where the actions should appear. However, you must pretend that you did. In most cases, this will mean that you will simply copy paste whatever you did on the menubarPath to the toolbarPath.

I am pasting a simplified version of the fillMenuBar method and the fillCoolBar one as well as a couple of plugins that add actions to those slots.

protected void fillCoolBar (ICoolBarManager coolBar) {
  IToolBarManager fileBar = new ToolBarManager(coolBar.getStyle());
  coolBar.add(new ToolBarContributionItem(fileBar, "file"));


protected void fillMenuBar (IMenuManager menuBar) {
  MenuManager fileMng = new MenuManager("File", "file");
  fileMng.add(new GroupMarker("start"));
  fileMng.add(new Separator());
  fileMng.add(new GroupMarker("end"));

With those method set up, you can add plugins (or just your RCP application xml descriptor) that use those paths:

<actionSet description="The action set containing some file actions."
  id="" label="File Action Set"
    <action icon="icons/my_icon.png" style="push"
      label="My Action" tooltip="An example action"

If you just add a couple more of those plugins, you will see that all the actions will be grouped both on the menu and on the toolbar.

And that's about it for now. Have fun guys.

Thursday, June 7, 2007

A tutorial for programmer

I think I will just have to admit that no mather how often I hope to publish news on this blog, I will always be late. But the fact is, running late is the only thing that pushes me to write here so I will keep trying to keep a reasonable pace and I will keep complaining about being late. I hope you guys don't mind.

As for now, I have some news although not many. Archimedes is quite stuck this week since today (thursday) is a holiday and it was half of our programming time. The other half was monday and we didn't used it to program for once. It was burned down making up a talk and a demonstration about how to develop plugins for Archimedes.
I've tried to keep all the documents in english so I could share them later on the internet but I still have a big work to do: the screencast.
The talk was composed of three parts, two of which I made and the first one was made by an Archimedes collaborator (Julien Renaut). It is mostly focused on programming problems and how people can add features to Archimedes. His talk was about extensions and extension points which are some concepts used by eRCP to allow plugins to add functionality to the main software. His work was done in Portuguese but I will translate it and insert it into the main talk I will upload.
The second part was my talk which was a lot more about Archimedes and how our main structure works. It tries to let people understand the flow of information within the software. It has a couple of "UML" (those are not really UML but kind of) figures and a nice review about Archimedes' main classes. I need to add the notes on this talk so that people can look at the talk and understand what I was trying to talk about.
The third and last part was a small example of how to create a plugin project that would add a new element to the software. This is quite a long work and I want to have a screencast of that with my voice explaining what is going on. So it will probably take me some time (maybe a month) to have it all working fine.

Also, there is a volunteer architect building up a user guide much better than anything we could ever produce. It is currently ongoing and is in Portuguese but as soon as it is finished, I will ask for help on translating this to several languages.

Speaking of languages, I am getting desperate to have Archimedes' build system working with maven 2 has said before. This would allow me to have a deploy once more as well as a nice translation zip file to have people translating the software more frequently and easily.

So that's what I've been doing. I've also been working hard to try to solve the problems from the uva gadget but I've been failing a lot which is not really keeping my moral up. :( Also, my desktop seems to have died on me. This doesn't means many loses at the moment but makes me quite upset and will probably take me some precious time to fix. Until then I might just not have anything to test Archimedes on Windows or Linux so I hope you guys keep sending us reports.

That's it. Bye bye!

Tuesday, May 29, 2007

A new release for Archimedes

I'm amost late AGAIN. At least this proves me something: I surely prefer tons of things before writing down to this blog. Sad but true, I'm not a writter, I'm a programmer.
Anyway, yesterday I've released the latest version of Archimedes concentrating several features I've been talking about such as Text, dimension, layers, etc...
We already found about 6 or 7 bugs during our demonstration to the architects that help us but this is only a proof that we should release unstable versions and have more people testing it. I hope make this possible by using maven to control Archimedes build and tests as well as the deploy system. Don't know for sure when this is going to happen but I will work on it in July.
I've tried to test the install system and the zip files on all three platforms and I believe everything is working fine but PLEASE tell me if something goes wrong.

Changing the subject, I've found out today how to write google gadgets and how fun this can be. I felt the need to find a gadget that would show me a UVa problem from the ACM contest each day so I could train a bit more since I wish to show a better performance on the local contest here in São Paulo this year. Looking up on their search system gave me nothing so I decided I could write my create my own gadget since Google has been asking people to do so since they renamed the personalized home to iGoogle. Checking out that feature I discovered it is only a very limited gadget factory aimed to non programmers but there I found the link I added at the begining of the paragraph.

I understood how the system worked (quite simple, it is just xml parsed into HTML code with javascript) and wrote my own gadget. I used google's users page to upload my gadget and there you go: I still wish to add tons of features such as a user id preference that would make the gadget load only problems you haven't solved. Maybe parse the site to create 3 tabs with description, input, output and maybe another one to submit a solution. I got tons of ideas and with Javascript, almost anything can be done (although it is very hard to design and debug it). For those of you who use google's personalized home, I do suggest you take a look on how to build your own gadget because I can bet there are gadget you would like to have that does not exists.

That's it for now,
Bye bye

Tuesday, May 22, 2007

Last week of release

Ok! I AM late!
I admit it. But at least I remembered.
Haven't got tons of news. We are entering the last week of iteration and basically this will be devoted to improve the software in a programmer point of view. This means we won't be adding features. The work planned is to improve the software's tests (that are kind of messy since the migration) and maybe focus on a better build system using maven2. I should release the version 0.52.0 late on Sunday or maybe early on Monday.
I could already give some insights. The first one is that we will be using the recently published truetype fonts from RedHat since they are compatible with the Windows core fonts and are GPL compatible. Those will be distributed with Archimedes to ensure full compatibility across platforms. I would like to thank gtroza for this tip.
The other one is not so good. We will not be delivering any persistence system yet. The old xml persistence system that existed previously is not yet ported to this new architecture because we are figuring a way to make it flexible enough to fit all our requirements. The PDF export is not ready either... Those will probably be the highest priority in the next release so it should be done in a month.
Mainly that is it about Archimedes. The rest I have talked about on the last few weeks.
I will probably not post any other news for the rest of the week since I will focus on having the release decently ready and tested not to have as many problems as last time. Again, no screenshot since you will be able to see the news by yourselves!

Bye Bye!

Monday, May 14, 2007

Almost one week later

Ups... I almost failed again to keep this blog up to date.
But recovered "on time". So, what are the news I have to share?

Well, mainly Archimedes news:
We are deciding if we launch the release this week end or the next one. This choice is mainly related to the free time people have to make this happen. The features that we had to develop according to the road map are not ready but a nice bunch is ok.

Just to be a bit more precise:
- The text feature is complete with an Arial font that is being packed with Archimedes. I still have to find out what are the legal issues about that and if I am allowed to distribute this. Otherwise we will have to find a cross-platform TrueType Font open-source or discover how the ones from OpenOffice are used. If anyone has any answer to those questions, please warn me.
- The layers are working again with the combo box and the layer editor window (with a lot of update bugs fixed).
- The Rectangle feature is back.
- The behaviour of the Orto system when you snap to Grid point has been "corrected". Which means that gripping has priority over orto.
- The Pan feature is back (although its shortcut through middle click isn't).
- Moving (or streching) by clicking on the snap points should be ready with a small amout of work.
- Dimensions are walking slowly but surely.
- The mouse cursor now changes when on a command. There is a big cross when waiting for a command and the small rectangle when you are on a command.
- The snap points are now dark red (just like the icons showed) and if you grip to any with the mouse, it will light up to yellow so that it is clear that you snapped.
- The infinite line is almost back. I'm just having a minor problem to render it correctly (meaning infinitely) but it should be solved quickly.

Features that we should have done and will probably be late:
- Zoom command
- Export to PDF
- Open/Save XML(.arc)

There are also several things we would like to improve in the programmer side. I can quote the build process that could be much better with Maven2, the deploy process that could be much better with continuum (or Cruise control), the test coverage of what we have done so far and a few other things.

I will probably focus on the simpler things now which are to finish the features that are almost done and, if I have some time, import the Zoom command from the last version.

I guess that's it. No screenshot this time... I'll let you guys holding your breath for the next release. :)

Tuesday, May 8, 2007

Combos as Contribution Itens on rcp

Okay! Maintaining the post rate for more then 1 day. My current record so far.
This time I will focus on a problem I had last week while implementing Archimedes' layer combo. Using combos in SWT is quite simple, you just create it linking it to its parent and add the texts. In an RCP application things are a bit more complicated since the widgets are positioned in the parent composite only when needed. This basically means that the ContributionItem abstraction is a closure to insert those widgets when needed.

I've implemented about 3 or 4 times this class because I had several problems and couldn't understand why since I got no exception message and the widget just wasn't being shown. I created this implementation thanks to an example posted in this mailing list ( by Jean-Michel Lemieux (author of "Eclipse Rich Client Platform: Designing, Coding, And Packaging Java Applications", one of the best books about eRCP I found). You can find a more complete implementation of this in Archimedes ( but here goes a simplified version.

public class ComboContributionItem extends ContributionItem implements
  IContributionItem {
  private Combo layersCombo;
  private CoolItem coolItem;
  private List texts;
  public ComboContributionItem(List texts) {
    this.texts = texts;
  public void fill (ToolBar parent, int index) {
    ToolItem item = new ToolItem(parent, SWT.SEPARATOR);
    Control box = createLayersCombo(parent);
  public void fill (CoolBar coolBar, int index) {
    Control box = createLayersCombo(coolBar);
    int flags = SWT.DROP_DOWN;
    if (index >= 0) {
      coolItem = new CoolItem(coolBar, flags, index);
    else {
      coolItem = new CoolItem(coolBar, flags);
    Point toolBarSize = box.computeSize(SWT.DEFAULT, SWT.DEFAULT);
  private Control createLayersCombo (Composite parent) {
    Composite top = new Composite(parent, SWT.NONE);
    GridLayout layout = new GridLayout();
    layout.marginHeight = 0;
    layout.marginWidth = 0;
    layout.verticalSpacing = 0;
    layout.horizontalSpacing = 0;
    layout.numColumns = 1;
    layersCombo = new Combo(top, SWT.READ_ONLY);
    for (String text : texts) {
    layersCombo.setLayoutData(new GridData(GridData.FILL,
      GridData.BEGINNING, true, false));
    return top;
  public void fill (Composite parent) {
  public void setText (String text) {
    if (layersCombo != null) {

I've cut the package and imports info but this should not be hard to add. I suggest you just copy this code and alter it to match your needs slowly so you see the result. If you have any problem with this code or need help because things are not rendering, please contact me.

With some minor changes on this code, I managed to enable the layer combo once again. Which means Archimedes is now back with Layers. The layer editor is still a bit buggy since the last refactoring but it should be solved very soon. I hope I have some nice screenshots by the week end with everything solved out.

See you later guys.

Monday, May 7, 2007

Archimedes on going & TrueType fonts

Keeping the speed is now critical. I am trying to make it a habit to write down every problem or achievement I have here so that people can benefit from those and I can get used to post more frequently on this blog.

Last week end I worked a lot on Archimedes to have the text problem solved. Mainly the thing is Archimedes needed to have a text feature so that users could write things on the drawing and the dimension feature could write the dimensions too. Last time we solved this problem, we had no idea about how to draw fonts on OpenGL and therefore the team chose to implement its own font system and fonts. This was heavily critized by the clients and users and by the developers too. So this time, we decided to implement it right. This means that we focused on reading existing fonts and what our clients asked was Arial which is a TrueType font. So we tried to learn how to parse ttf files and then find out how to render those.

After some research on the internet about java ttf parsers we found an interesting Apache project called Batik. This project focuses on SVG support to a lot of things and, especially, having truetype fonts ported in svg paths. Thanks to the Apache Software license (thanks free and open source movements) we were allowed to read the source code, modify it and use it in Archimedes. So after a couple hours studying the code, we grabbed the packages that were in our interest and brought them into an RCP plugin and used them in Archimedes.

Now a few comments about truetype fonts. The Font class in batik that encapsulates a TTF font is mainly formed of 10 or 15 tables that contain infos about the glyph (characters), platform and several other details I don't understand decently. What we needed to use the font was just the cmapTable and the cmapFormats. Those classes contained mapping between several encodings to the glyph number in the font. Also each point of the glyph contains information about whether it is a normal point or an "endContour" point which means it is the last point of a circle and should be connected to the first point non "endContour" found. We also learned (although we didn't implement it) that interpolation between those points should be done with a bezier curve of second degree but this having this on Archimedes is probably an overkill at the moment.

Dropping a bit the technological part (all the code can be found in the package and class), all this information means that the software is now loading a truetype font and rendering it with OpenGL. There are still a few problems to fix like mapping weird characters and having this working perfectly on all platforms but all the rest is working fine. And here is a small screenshot just to prove I'm not lying:

Sunday, May 6, 2007

Loading files with RCP

Keeping my efforts to post about interesting things instead of just complaining most of the time like I use to do, today, I will write about how discover the file path of certain files from within an RCP application.

First of all, the problem of loading a file in that situation must be explained. It sounds a bit stupid to explain something if it seams there is no problem to solve, right?
So, loading a file when you are coding an RCP plug-in is a problem because you can never know where your application will be relatively to the plug-in. You could hack some way out of this by assuming some things about your platform since eRCP, by default, generates always the same structure. But the fact is that this could be broken by just a few minor changes on your platform. So if we want to solve the problem correctly, we have to rely on the main application to load things correctly since it knows exactly where it is and where the plugin is.

Now that the problem should be clear, let's understand what is eRCP solution to it. The first simple solution presented is implemented in the default Activator class eclipse generates for each plugin if required. This class contains a static method findImageDescriptor that loads an image with a relative path. This is very useful since most plug-ins have some kind of image that they wish to load (icons, images, etc...) but it obviously does not solve the problem of loading any file. This operation is a bit trickier because it is pretty well decoupled so that people can load things at the level they desire.

Before version 3.2, eclipse (and eRCP in general) suggested to use the method "find" implemented in the Activator class reachable from Activator.getDefault(). Since version 3.2, this has changed and that old method is now deprecated. I don't know the reason for sure but I would guess that they found out that the Activator class shouldn't contain knowledge about how to load a file. The fact is that the static class FileLocator was created to encapsulate that knowledge.

Now that class is quite simple to use and it is probably not a problem to find out how to use the FileLocator.find(Bundle, IPath, Map) method. Most of the time, you will get the bundle from you Activator class (getDefault().getBundle()) and the Map will be empty because you probably want to load a file that has no dynamic info (otherwise, check the javadoc to know how to use it). Most commons uses of this method will just instantiate a new Path with a String argument that is the path to the file relative to the plug-in's root folder. This will return you an URL instance containing the info about your bundle and the file's path. If you check it, you will notice it is not a normal path but something like "bundleentry://bundle_number/path_to_your_file". As you can guess, there is no way you can use that to instantiate a File or a FileInputStream to read it.

And that is the hard part: You will find two static methods in FileLocator that can help you:

In most of the cases, both method will return the same correct path. But what is the difference about them? I am not sure so please do not take this info for the truth before looking for more information. From my viewpoint, the difference regards only the path you will get at the end. The first method will return URL with http, ftp, jar, etc.. protocols while the second one will only return file protocols which is, in most cases, what you desire. Having tried to explain all this, here is the code you will get to load a file from your RCP plug-in:

Bundle bundle = Activator.getDefault().getBundle();
Path path = new Path("path/to/your/file.extension"); //$NON-NLS-1$
URL url = FileLocator.find(bundle, path, Collections.EMPTY_MAP);
URL fileUrl = null;
try {
fileUrl = FileLocator.toFileURL(url);
catch (IOException e) {
// Will happen if the file cannot be read for some reason
File file = new File(fileUrl.getPath());

I hope this helped you guys and please feel free to ask any question if I wasn't clear on something. See you guys later.

Wednesday, May 2, 2007

More errors & Archimedes screenshots

People always say we should do things while rested and without rush. Otherwise we will screw everything and make it all go wrong all the time. I never really listen to those advices although I really believe they are 100% correct. That is a BIG mistake!

This BIG mistake made me screw out two Archimedes' releases in a row. 0.50.0 was a crap because the zip files were trash and the linux (and windows) installers and zips did NOT contained the OpenGL plugin required to be able to see any drawing. The next day I was there, tired again, trying to fix all the problems and, as it should be, I fixed a couple of them but never even realized that my regular expression to match the openGL plugin was NOT matching with the windows plugin. Just to have a last cherry on the cake, I found out later on (at work) that for some mysterious reason, the linux opengl plugin was generating a nice and friendly crash regarding something on the native library. So great!

This means I will release later on today yet another version of Archimedes with not 1 more feature just trying to have the bloody files to work! While I don't complete this work, I will attend to a request from a greek reader to post some Archimedes's screenshots. I took those using the deploy generated by pde for that next version. Let's hope my script will not screw everything up once again! If it does, I will be forced to stop all development and have Archimedes' core and all the plugins compiled and tested by maven2. This should solve my problems at least for some time.

The first screenshot is a clean view of a drawing on MacOS X (from my development laptop):

The second screenshot is a view of Archimedes with a nice very simple drawing during an arc creation on Ubuntu (GNU/Linux):

The last one is the layer editor view of Archimedes on Windows:

We will probably have nicer and better screenshots after the next release (in about 3 weeks) and I will update the ones at sourceforge and those ones then. For now, this is all. I will be back as soon as possible.

Script errors & eRCP shortcuts

Let's see the good part of things: I'm posting a lot more on this blog (if that is somehow good). But as I started announcing good parts, it is quite obvious I did something wrong. Well, I screwed the script that generates Archimedes's installers. The result was that the generated zip file was all messed up with the path. Also, the installers were not adding most of the plugins with operations because I forgot to add the entries into the core. So I decided to add a package with those. I should probably enhance that system though. Too bad I won't do it so soon.

Anyway, back to what is important. Retaking that old series I promised about Eclipse Rich Client Platform. I'm going to talk a bit about the new shortcut system on eRCP. I thought this might be usefull because Archimedes' developers will have to do this a lot and a friend of mine was asking me about this and couldn't find anything around.

First thing people will notice when having to handle with shortcuts in eRCP is that all action has a wonderful "accelerator" field which seams to make this help useless. Unfortunatly, if you use that accelerator you friendly get a warning message and once you take a look at it, you'll find out that it is deprecated. Well, as you all should know, deprecated means that you can use it... for now! You have absolutely no guarantee that in a couple weeks it will still be there. Therefore we should try not to create new features with things that might disapear in a couple weeks. So we agree that we should find another solution to it. Great!

Make some research you find out that there is a new way to do accelerators that is much more flexible and powerful. The only problem is you hardly find any example or tip anywhere. After having suffered a lot to find how it should be done, I reached this not so simple way but indeed much more flexible and powerful. Here is an example from Archimedes:


What this xml does?
Basically defines two new extensions: commands and bindings.
The idea is that each command can have several bindings or diferent bindings for diferent languages or platforms, etc...

Why do you need those?

What you really want is the binding extension which defines a binding between a command and a key sequence. Of course, you need a command in order to have this binding. That's why you need the command. Now, if you pay attention I had to create a new class (OrtoHandler) to deal with the key match event. This class has to implement IHandler interface that is a publisher that allows subscribers to listen to that event and informs whether it is able to run or not and has a run method. In most cases, this will replace or be the same class you used in your Action.

There you go. Now it is easy to define accelerators for your eRCP applications.

Sunday, April 29, 2007

VoIP wonders

The last couple month have been very happy months.
I got my beloved macbook pro and got a wonderful gift from Kristian Kielhofner (founder of astlinux distribution): a small thin client (a.k.a the box) and a small phone/ethernet converter box (a.k.a the black box).
Now, those small boxes are just great. During the fisl 8.0, Kris gave me a not-so-short class about asterisk and how to work on those two boxes. Since I've been so busy, I had not had the time to have fun with them but this weekend I decided to make them work.
It took me no longer then 3 hours to have the box plugged to the cable modem, the wireless router plugged to the box working as a hub and both the black box and my desktop plugged to the router. Meaning that my whole network was running behind the box.
So far, nothing great about this right?
The great part starts now. With some help from Kris, I logged on the box and set it up to recognize the laptop's softphone, the desktop's one, my mom's laptop's phone and my home phone. Meaning that I can now, make or transfer calls from any of those to any of those. Sounds useless at home I agree. But just think about what this can do if you have a small/medium business and can't afford a PBX company (since those are REALLY expensive). You could have your whole internal communication running over your ethernet network. Let's agree on a couple things here: less cables == less pain/troubles. And the best part, this can work if you are not all the time at your office. As long as you have an internet connection, you can receive your incoming calls and people will never know you are not there. This really owns!
Following those ideas, thing about how much it would cost you to call someone in another country. The answer is simple, the local phone call from an asterisk server in that country to the phone you are calling. This is exactly what I paid to chat with Kris for about 20 minutes this afternoon as a test for the system. Except maybe that I paid nothing, more likely, Kris did. But again, this could be changed. The fact is, people could easily call my home number and dial a couple of extension to make phone calls to their beloved ones that have a good internet connection paying just a local phone call. Just imagine how great this is. It just means we are crossing another line. Years ago, the phone system was getting fans all over the world because people could speak to other people all over the world just like if they were 10 feet away. This was indeed wonderfull but it also turned out very expensive. What we are reaching now, is a cheap simple way to get all those people connected to each other.

This just amazes me. I am now for sure a fan and will become as soon as I can, a good user and maybe even a developer for those open source solutions. And once I get all my system set up, I will post a few other details and maybe I could get my config files somewhere to help anyone that wishes to try it out.

Archimedes Road map for May 2007

It was quite obvious I am not ready to maintain a blog yet. But I will keep trying anyway.
At the moment what I have to say is that publishing a new version of Archimedes is a time taking operation. Besides from generating all the releases and zips and uploading everything to the internet both Sourceforge and CodigoLivre and manually having to upload the same files to a couple of other sites, I have to generate about 10 texts that should be published as news on those websites, mails on the releases mailing list, comments on the change log and release infos and a web page to be added to the Archimedes website.
All this work can be very time consuming and gets me very tired and bored. At the moment I have an automated system working with Eclipse PDE and bash scripts that allow me to generate the deploy and the zips and installer and upload all those files to the sourceforge and codigolivre. It basically runs an ant call on eclipse to do the pde work and then works with zip and ftp to generate the files and upload them. Took me about 1 hour to make since I'm a crappy shell scripter but now it's done. So that's the quick part now, but I still have to upload files one by one two sites (codeplex and incubadora) which is a very slow operation and I fall in the old problem: generating all those texts.
As anyone can notice, I am a REALLY crappy english writter and my teachers usually say the same about my french or portuguese writting skills. That can comforts me since I usually generate those texts very fast since I know it will suck anyway but it still takes a lot of time and energy. Especially when I have to translate some parts of it. Anyway... enough complaining.
About Archimedes, the next release should be launched may 26th if nothing goes wrong. This would mean about 1 month between both releases although I would really like it if we had news to publish weekly from now on (meaning next week should have something new to users). The plan for the next release includes:
  • Text and Edit text working with Truetype fonts loaded from the system. This should allow users to use the text feature for real, not just like it was before.
  • Simplified Dimensions with the hability to reposition the dimension's text. We might not have the time to get this completed since it depends heavily on the text to work decently.
  • Layers should be back with all the old features and maybe even some improvements.
  • A small "bug" on the snap behaviour with orto on will be fixed. This means snap will overrule orto if the mouse grips on some snap point.
  • Moving will be enabled when selecting certain snap points for certain elements.
  • Saving and Opening files on the Archimedes format should be back also.
  • PDF Export should also be back to allow users to print their work or just show it to someone else.
  • Rectangle, Zoom and Pan will also be back but those have no improvements planned yet.
This should be about it. It is not a lot and we might even get some few other features implemented but all will depend on how the team manages to work on the next few weeks. I will try to post a bit more about it as soon as possible.

Monday, April 2, 2007

Can't keep promisses

Okay! I admit it: I can not keep my promises regarding publication.
This is clear when you look at the blog's history and at the Archimedes' history.
So I'll try not to make any other promise. (Remark I am not making it a promise)

Anyway, regarding the automization process of Rich Client Applications: I found a nice article about using maven2 to make the whole build and testing process. You can find it here. My next mission is to take a deep look in that article and try to make archimedes use this.
It would deeply improve the build creation and maintenance and would allow me to use a continuum (or similar) server to deploy up to date sites with documentation.

Other then that, Archimedes is, at the moment, more or less like it was in version 0.6.0. This is aproximately the current status of features. The new atempt is to publish a "stable" version april 16th but I am pretty sure it will lack some of the most important features.

Anyway, that is about it. I'm using about 25% of my coding time to try and keep this blog and the sourceforge news up to date which means I am programming much less then I would like but since so many people pointed out that the projects infos should be always updated, I am doing what I can to keep this true.

I hope I'll be back next week with more news.

Tuesday, March 6, 2007

In love with my MacBook Pro

I'm sorry I'm late with posting my article about automating your build and installer generation. There are two main reasons for that. The first one is that I have to learn how to do it before I can write about it. I kind of have an idea about how to do it but I should start to write a couple script and test it before I write a load of craps about it.

The second reason is that I just received my brand new MacBook Pro. This is mainly taking most of my time since I want to try every feature I discover on it. Totally got me impressed. As many say, once you try a Mac, you think twice before coming back to another OS. I could tell you that, for sure, I'm going to stay REALLY away from Windows since the only thing I used to do on Windows was playing games. But since most games I play are available for Mac, really no need to use Windows.

I wouldn't go as far as to say I'm quitting Linux that fast however. I surely believe Mac OS X is a much nicer Desktop interface and since it has a sort of Unix core I can use most of my scripts and things in it.
There are some limitations however and the problem of losing some freedom. I am, however, very pleased to see that, for once, I paid for something that was worth it. Very stable, very nice, very pretty, lots of cool features and cool softwares.

For sure I now recommend Mac for people who don't give a damn about freedom to alter the code (since usually they don't even know what "the code" is) and want a very productive and good interface.

If some day (and I doubt it) Mac opens their source code, I would consider it the best OS for personal computers anyone. Some miles ahead of Linux and some year lights ahead of Windows for sure. I should here apologize to the Gnome and KDE developers, you guys are doing a freaking good job, but Mac OS X managed to accomplish an amazing work and the Leopard version (to come yet this year they say) should bring the little features I'm missing a bit using Tiger.

Anyway, as you can read, I'm totally thrilled about my new computer so I'm a bit behind schedule on any thing while trying to have it fully configured for extensive use. If I don't have the next post ready until the week end, I promise I'll do it for Sunday.

Wednesday, February 28, 2007

Creating a multiplatform installer (with IzPack)

Hello once again.
As promised, today I'll talk about how to create your multiplatform installer for your Eclipse Rich Client Application without having to add all the folders PDE (Plugin Development Environment) created.

First of all, understand that what I'll explain for IzPack can be used for any other installer you like. Just search for a feature similar to the one I quote in your installer and you should have no problem.
Now that this is explained, let's get started:
First of all, part of your jobs is already done thanks to the eRCP imposed architecture. I'm talking about having your project split in several parts that are almost completly independent. This is very useful since it'll allow your user to choose the plugins he wishes to install.
This reminds me of something: feature != plugins.
Your update site or your product uses a set of plugins and call it a feature if you followed most of the tutorials. This doesn't means your installer must care about your feature definitions.
The feature definition will allow your update system to know which updates it should look for and which features are considered "new features". This means that if your application is running without any feature and you ask for an update, it'll show you the core feature (which you obviously already have since you're running your application) as a "new feature" to be installed. That can be explained by the fact that sites only know about features and never look to plugins.

Therefore, a good practice is to have your core feature as a required package in your installer. Any other feature you would like the user to update through the update system should also be joined as a package in your installer. However, if you wish to offer the user the choice to install only one plugin regardless what is its feature, you can do it without further consequences. Your application will work without a problem and with this plugin activated.

So, you have decided what will be the packages available in your installer. You must know what license you'll use and you can have a couple shortcuts because it's always useful.

Now let's produce the XML file that will explain to IzPack how it should work.
Your first section of the IzPack XML should be the something like:

<appname>Your App</appname>
<author name="Tarantulus Corp." email="" />

No big secret on that. It defines mainly the first screen post language choose. Excepting 'webdir' all those fields are shown in that screen. The 'webdir' is the addressed used to search for the package if you are about to create an online installer. This is mainly the only thing that changes from a local installer to an online installer in IzPack.
The second part of your XML should be:

<guiprefs width="640" height="480" resizable="no">
<modifier key="useButtonIcons" value="yes" />
<modifier key="useLabelIcons" value="yes" />
<modifier key="langDisplayType" value="native" />
<modifier key="headingPanelCounter" value="progressbar" />
<modifier key="headingPanelCounterPos" value="inNavigationPanel" />

This is a bit more obscure. The first lines are quite easy to understand. 'landDisplayType' is not that easy however. It sets how the installer will show the options of language to the user on the first screen of your installer. In this case, native tells the software to use the system's locale to write the languages. 'headingPanelCounter' and 'headingPanelCounterPos' defines how the steps remaining and the current step should be shown to the user. If those lines are not present, nothing will be displayed.

Next you have:

<res id="installer.langsel.img" src="installer.png" />
<res id="LicencePanel.licence" src="license.txt" />
<res id="shortcutSpec.xml" src="shortcutSpec.xml" />
<res id="packsLang.xml_eng" src="packsLang_eng.xml" />

Okay. Now we're talking! First of all, the image to be shown in the first screen of the installer is the one on the first line. The license that will be displayed to the user and that he will be forced to accept unless it quites the install. Beware, this license should be in a text format because IzPack will display it as a text only file. The last lines regard the shortcut creation and the internationalization of this installer. Take a look on the official documentation and this should be enough.

The next part is what will define the flow of your IzPack installer:

<panel classname="HelloPanel" />
<panel classname="LicencePanel" />
<panel classname="PacksPanel" />
<panel classname="TargetPanel" />
<panel classname="InstallPanel" />
<panel classname="ShortcutPanel" />
<panel classname="FinishPanel" />

Those panels are available by default in IzPack. You can, however, create your own panels as well as install new ones created by the community and available mainly at IzPack's site (

At last, the last part is the most important one. The one that will specify each pack of your application:

<pack name="Core" id="core" required="yes">
<description>The core of Your App.</description>
<fileset dir="@{deployDir}/win32.win32.x86/YourAppName/" targetdir="$INSTALL_PATH">
<include name="startup.jar" />
<include name="configuration/config.ini" />
<include name="features/org.eclipse.rcp*/**/*" />
<include name="features/*/**/*" />
<include name="plugins/**/*" />
<exclude name="plugins/*.jar" />
<exclude name="plugins/org.eclipse.swt.*linux*.jar" />
<exclude name="plugins/org.eclipse.opengl.linux*/*" />
<exclude name="plugins/org.eclipse.opengl.linux*/**/*" />

<fileset dir="@{deployDir}/linux.gtk.x86/YourAppName/" targetdir="$INSTALL_PATH">
<include name="icon.xpm" />
<include name="yourapp" />
<include name="about.html" />
<include name="" />
<include name="about_files/**/*" />
<include name="plugins/org.eclipse.swt.*linux*.jar" />
<include name="plugins/org.eclipse.opengl.linux*/**/*" />
<os name="linux" />
<fileset dir="@{deployDir}/macosx.carbon.ppc/YourAppName/" targetdir="$INSTALL_PATH">
<include name="**/*" />
<include name="plugins/org.eclipse.swt.*macos*.jar" />
<include name="plugins/org.eclipse.opengl.macos*/**/*" />
<os family="osx" />
<fileset dir="@{deployDir}/win32.win32.x86/YourAppName/" targetdir="$INSTALL_PATH">
<include name="yourapp.exe" />
<include name="plugins/org.eclipse.swt.*win32*.jar" />
<include name="plugins/org.eclipse.opengl.win32*/**/*" />
<os family="windows" />

<!-- The windows scripts -->
<executable targetfile="$INSTALL_PATH/yourapp.exe" stage="never">
<os family="windows" />

<!-- The Linux scripts -->
<executable targetfile="$INSTALL_PATH/yourapp" stage="never">
<os name="linux" />

Each <pack> must have one or more files registered. Those can be added using the file tag (when you want to work with one specific file) or the fileset tag (when you want to work with folders) as shown. The fileset accepts both <include> and <exclude> tags which allows you to easily create exceptions in your folders. Also, all those tags accept <os> that will be interepreted as a mark to tell the installer on which OSs those files should be unpacked. This is mainly how you separate things. The first fileset defined in the example above is the one that grabs all non-OS specific files from the RCP. The next 3 filesets are used to select os specific files as the 'os' tag shows.

At last, the <executable> tag marks the file you target as executable. This means a double click or a command will try to run those files. This is required because the installer will zip all the files in jars and loose all kind of permissions over the file on install. So it needs to know which files should be diferent from the read and write permissions.

All this should allow you to create a simple multi platform installer for your eRCP application. Once this is done, you'll probably want to add the <locale> tag to add internationalization support to your installer and then you'll need to create some language specific XML with pack descriptions translations and everything else.

A last tip, beware to export all of your features and plugins when you are in Eclipse. You'll need all the files available on your deployDir to make the installer work well.

The next post will discuss about how to create all the application, the installer and transfer all to a website using one simple script. This allows a much quicker and constant deploy of your software to your users. Expect it done for saturday or sunday.

See you guys soon. Bye bye.

Saturday, February 24, 2007

How to export multi-platform?

I hope that after those last two posts, you are already capable of adding your classes to your project and growing it without any further problems. Once this is done, I also expect that you can export your project and run it outside of Eclipse with no headache. You choose your deploy directory (which I'll call $DEPLOY_DIR) and you can run your executable software at $DEPLOY_DIR/yourapp(.exe). If this is not the case, feel free to contact me either by email or posting a comment.

So, now that you have your development environment set up and you can run your software in your platform, you probably want to export it into other operating systems (OS). For now, you don't even have this option anywhere you can find it. If you search a bit through the internet you'll discover you need the RCP-Delta-Pack to do so. Very good... but where the hell is that pack? If you search around the RCP download you'll eventually find it although it's not really very well exposed.

The way to find the up to date version is:
Choose "Other downloads for ..."
Get down to "RCP SDK" and the last file is the RCP delta pack.
For the 3.2.2 version, just click here.

Now that you have your delta-pack, it's really easy. Just unzip the file into $ECLIPSE_HOME/plugins and restart your eclipse. Now when you ask to export your application, you'll get a nice checkbox asking if you want to export to multiple platforms. If you select it, the "next" button will become active and if you click it, you'll have a list of supported OSs. Let's say you'll select macosx_ppc, linux_x86 and win32_x86 (like Archimedes does).
The export system will use the $DEPLOY_DIR and create in it, 3 folders (one for each system):
And each of these folders will contain all files needed to run the software on these OSs with those graphical interfaces.

If you take a look, you'll find that much is common to all OSs and we hope so, since it should be a platform-independent software. I cared to take a deeper look and list what is common and what is not.
Mainly, the "configuration" and "features" folder are identical. The "plugins" is mainly identical, the only thing that may change is a couple of plugin fragments that are OS specific (like "org.eclipse.opengl.linux" and ""). If the fragments have requirements regarding the OS, they will be selected only by the OSs that support that requirements. Careful about that! If you depend on a plugin that has a fragment like that one and it doesn't get exported, you'll get the friendly "There was an error. Please check .metadata/.log for more details." message. If you check the log, you'll find the also friendly (but known already) "No application ID found" message.

The root folder, however, is quite diferent depending on the OS you look. The only file that is always available is "startup.jar" which contains the basic RCP plugin system which will activate whatever needs to be activated.
All the rest is quite diferent. For example:
Windows has only a "yourapp.exe" file.
MacOS X has a whole folder "" with a nice deep structure required to make your software run like a native Mac software.
Linux is the most poluated one. It has "youricon.xpm", a folder "about_files" and a page "about.html", "" and a "yourapp" executable file.

Now why is that important? Because you will probably want to make an installer (like Archimedes does) or a common package that would allow your users to download once the core and add the OS specific files as they need it. In this case, you'll need to know what is core and what is OS specific.

I'll stay here for today but my next post will be about creating this installer. I'll use IzPack ( to make the example because it's what Archimedes uses and it is very simple and powerful. You can probably, however, use the example in any installer you'd like just adapting the procedure.

Thursday, February 22, 2007

Your first problems with RCP

Now that we had a good start with RCP, we face a couple of problems upgrading our application. First of all, if you are a curious person (and this is a good thing), you might be facing a couple of problems while trying to run your application from outside of Eclipse.

Problem number 1:
You can run your application from within Eclipse but when you try it outside of Eclipse you get a: "No class definition found ...".
If you are having this problem and the class that can't be found is one of your own, you probably made the wrong move! Check on your MANIFEST.MF file if you have a line: "Bundle-ClassPath:".
If you don't, you have gone even further that I though. Add it quickly!
If you have it, check that the path '.' is there. You MUST have '.' as a class path for your application or else none of your classes will be found.

Okay! That was easy to solve now that you found the solution.
You move along and you get challenged again:

You probably created your first RCP application with a product that was based on plug ins, right? Now it's time to move it to feature based architecture. Great! That will enable your application to benefit from the update features.
Go ahead! Change your product file to be feature based. Once you done that, all works perfectly within Eclipse but, again, when you run it outside, it does not works.

Problem number 2:
You can run your application from within Eclipse but when you try it outside of Eclipse you get a: "No application id found ...".

Okay! First thing to do, check the plug in folder from your application. It should contain all plug ins that are necessary to run you application. If one plug in is missing, you get the "No application id found ..." message.
If this does not help you, try opening the file "$YOUR_APP_HOME/workspace/.metadata/.log" with the Error log view in Eclipse. Take a look at the most recent entries. You should see the "No application id found ..." message and some warnings surrounding it.
Take a good look over the warnings looking for one of them that says something about "Bundles missing". It should be extensible. Extend it twice, you'll get a list of missing bundles. Those are the plug ins that the RCP is trying to load and is not finding. Search for errors within those plug ins or if they are available. Once they do, it should restart working once more.

Wonderful! So now you are feature based and your application works perfectly well inside and outside of Eclipse. Time to create an extension point for your application. Eclipse really helps for that. It creates all the necessary files for you and you can focus on whatever you want.

Problem number 3:
You want to define your extension point and you would like it to have children. Like in:

<extension-point id="myapp.myext">
<myext id="ext3">
<status name="fileSystem" />
<status name="swap" />

First of all, when creating your extension point, you'll find out that PDE 3.2 won't let you create a new definition within the extension point element. Don't worry! That's normal. It just doesn't create the xml tree at definition it understands when you use it. Second thing, just like the extension point, you can't create a new definition within your extension-point. Again, same procedure: ignore it and create it after your extension point definition but use it inside and all will go fine.

Now you have your extension points created. Time to create a new project that will extend this point. Go ahead! It's a good idea. So you start and once you done the whole thing you get a warning: "Illegal child element ..." at your "plugin.xml".
Well, my tip: Ignore it! It's a know bug from PDE 3.2 that is already fixed at the repository.

Well, those must be the first problems you'll face with RCP and probably the once you'll loose more time. After this, you understand the errors a bit faster and starts not getting stucked for stupid reasons like I did. :)

If you have other problems with or without solution, please post them and I'll do my best to help or to spread the solution a bit more.

Enjoy yourselves!

Saturday, February 17, 2007

Why Eclipse's RCP?

Well, let's start producing something interesting:
First of all, there are two things that you may be thinking of doing that will make you choose to work over Eclipse's Rich Client Platform (eRCP from now on):
  1. You want to develop a plug in for Eclipse. In such case, you have absolutely no choice. You will have to work over eRCP. On the other hand, you will be doing a lot of things that other persons already did and you will find several tutorials and samples that can help you.
  2. You want to develop a standalone application of your own. This will be the focus because it's doing this that you will find most problems.
Okay then, you want to develop your standalone application.
Why should or shouldn't you work over eRCP?

Mainly, what you will gain from working over eRCP is a very strong extensibility for your application with a great architecture as well as a very decent internal update system and a nice help system. Wow! Wonderful right? And there is more! If you start now, you get a "native" cross-platform application for free!

Ok! I got a bit too far with that last sentence. So let's keep cool, not all applications are meant to be developed using eRCP. So what are the counters?

You will spend some time learning how eRCP works. And when I say some time, I mean something like 3 or 4 days totally lost doing things you don't really understand how they work.
You will also have some megabytes inserted into your software even before you have anything working. To get an idea, if you use all the features I quoted before, before you have any code of your own, your application will already have some 16 Mbs. If your application is meant to be light weight, forget it!
At last, you will have to adapt to eRCP's architecture and believe when I say it: It's a very very good architecture but it forces you to achieve, at least, a very good architecture level. This may take you some considerable time (I'm still trying to reach it).

So, okay, when should I use eRCP than?
When you want to develop a pluggable application, flexible, very strong.
When you want/need a very good Internet update system.
Let's say the help system is a bonus because it is not that hard to do in any standalone application.

And when shouldn't I use it?
When you want things to go quickly, you have little time to do your little application.
When you don't need plug ins.
When you have limited memory or processing.

Okay! But you don't like IBM/Eclipse... is there an alternative?
Yes. Sun Microsystems has the Netbeans Rich Client Platform (nRCP). It has almost all the features eRCP has but you'll loose a bit of community support since it's much less widely used and you'll win good documentation because Sun manages to have some very competent documentation writers.

Now that we are set about what is Eclipse Rich Client Platform, I'll leave you some links where you can have more insights about it: (RCP's faq and official RCP's site) (The first part of a trilogy article from Ed Burnette. Very useful to start with RCP) (an article to read after Burnette's one by Andrew Eidsness and Pascal Rapicault) (The best book I found for eRCP though it's not free)

Of course you can find much more looking over the Internet for "Rich Client Platform Eclipse" or "Rich Client Platform Netbeans" or just "RCP your-topic".

The next step is to start developing your own RCP application from scratch but you'll have to wait until I'm back from the Brazilian Carnival for that. See you next week!

Thursday, February 15, 2007

Initial post

My name is Hugo and I'm a brazilian programmer but I'll write this blog in english for some reasons. The main reason for that is that I wish to share my programming and coding experience with as many people as possible. The second reason is that I really need to practice my writting in english (in other languages also but I'll handle that somewhere else).

I should have explained this earlier but this blog will be used to report several information about my programming experiences and problems faced. Most of my code is written in Java so you'll find a lot of infos about Java specificities and platforms available for it.

The main thing that drove me to start this is the lack of information there is about Eclipse's Rich Client Platform. I found several problem using it and I wanted to share those experiences. Another important part of this blog will be dedicated to Archimedes. I started this project almost 2 years ago (around july 2005) and I'll use this blog to give some infos from inside it's development.

This should be the main road although some things may come out of it from time to time. Of course, all comments and critics are welcome (even if it regards my crappy english spelling and grammar).