The Java Redemption

GWT incompatibility with Karmic Koala

2009-11-03T12:45:00.001+02:00

After upgrading to Karmic Koala, the GWT Hosted mode browser stoped working (it couldn't even launch) due to a missing libstdc++5 library. Obviously Ubuntu 9.10 uses version 6 of the library, so a temporary but working solution was to install version 5 too from the Jaunty repositories. I found the solution here and verified it with past.

Ubuntu 9.10 upgrade

2009-10-31T20:10:00.001+02:00

The home pc has just been upgraded to 9.10. Every time I install a new ubuntu I try hibernation. I have never managed to make any of my linux machines hibernate correctly. This time it was different. The machine seemed to hibernate and power off. Well my joy didn't last though. When a tried to resume, a blank screen was all I could have. Never mind, Karmic Koala seems nice and a night of exploration is ahead.

Links for 2009-10-15

2009-10-15T13:26:00.001+03:00

Put.io is an innovative new cloud storage service

October 7, 2009

2009-10-07T15:54:00.001+03:00

JDK7 do escape analysis by default | Java.net

GO2WEB20 Blog: Google Wave: First Impression
... and not a good one

September 24, 2009

2009-09-24T17:58:00.001+03:00

The Duct Tape Programmer - Joel on Software
This is absolutely right (and funny). I would like to copy some good extracts here but there are so many, I would have to copy the entire article.

Google Web Toolkit Blog: Delivering faster, richer GWT applications to your users
GWT is ready to use the webkit inside IE, provided by the Google Chrome Frame plugin. I wonder if our corporate clients with the strict policy on software they use, are willing to install the plugin...

What Did I do for One Web Day (aka. Why Should the Government Advance its FTTH Plans)

September 2, 2009

2009-09-02T11:09:00.001+03:00

blog dds: 2009.09.02 - Job Security
Really funny HOWTO make yourself indispensable by writing code that noone wants to maintain. Of course, dds is obviously joking.

Links for 2009-09-01

2009-09-01T11:15:00.001+03:00

Aza’s Thoughts » You Can’t Multitask
"The net effect is that it takes more time to multitask a set of actions than it does to do them sequentially."
True.

Saturday Morning Breakfast Cereal
How science reporting works
(where 'science' can be replaced by 'any')

Applications meme

2009-03-20T23:17:00.002+02:00

I usually don't take part in these kind of meme games (actually I have never) but this time I thought I could make an exception. Not that this meme is less silly or less absolutely useless than others but for some strange and unexplained reason I found it interesting to try and answer those questions about software I use. So here it is:

1. Which desktop manager do you use more often ?
I use Gnome just because it is the default in Ubuntu and experience has taught me to keep the defaults otherwise trouble is lurking in the shadows.

2. Which desktop application you would not like to see implemented again on linux? And why?
Normally, I wouldn't answer this one because I couldn't care less. At the very last moment though I remembered how annoying it is to have 4 or 5 different media players on my linux machine, each one designated to play a certain type of files. Plz don't create another one. Instead try to make one of the existing ones play everything.

3. Which desktop application you definitely would like to see implemented on linux? Describe it briefly or point out to a similar application.

A decent application for synchronizing my mobile device (phone or other) with evolution or the google calendar.

4. Write the name of the last project (not the very best, the last!) that made you wish to thank their developers so you can thank them now!

The scrobble function in MediaPortal :-) I know it 's a windows application but the question doesn't say it has to be linux.

5. (Optional) Link the blogs of 1-3 people you’d like to take part to this meme. (no more than three). you can skip this question if you like.

What? You mean the others were mandatory?

The case of the WrongClassException

2009-03-13T11:24:00.002+02:00

Yesterday, one client reported a strange bug in his application. It was an org.hibernate.WrongClassException during loading of some pojos from the database. I should mention here that the application is EJB3-JPA based with SmartGWT for the front-end. The exception was thrown when trying to load a specific object of class A and hibernate reported that the object was already loaded in the session but it was of the wrong class (class B). After playing around the database and the pojos annotations I saw that the two classes were subclasses of a common class and that the @Inheritance(strategy=InheritanceType.TABLE_PER_CLASS) annotation has been used on the parent, meaning that the two subclasses were mapped onto separate tables. I luckily remembered that in that case the primary keys have to be unique among the two tables even though we are talking about separate tables, otherwise hibernate will get confused when an object from table A is already loaded and it tries to load an object from table B with the same id. It thinks that the object is already loaded but it is of the wrong class. The odd thing in my case was that the two tables actually had different keys!!! What had happened as I discovered later was that the client had added some lines in one of the tables without caring about the key uniqueness between the two tables, thus leading to the WrongClassException problem.

Conclusion: Never allow the client touching the database!!!

FireStatus 1.5 meets Del.icio.us

2008-11-27T23:28:00.009+02:00

FireStatus 1.5 is out and it supports saving bookmarks on delicious. If you select the delicious checkbox a second text line will appear to enter tags for the bookmark. You don't have to select the "include url" checkbox for delicious unless you want to send an update to the other supported services. Delicious support also includes receiving bookmarks from your friends on del.icio.us in the usual way with popup notifications.

In the preferences, you have to give your delicious credentials and set the interval for polling for bookmarks from your friends. Be careful not to set interval to less than 30 minutes because you risk being temporarily throttled by the service.

The future
The next feature to be implemented is a list of all updates received from all enabled networks. Popup notifications are popular but if you miss one there is no way to see it, so the plan is to have a list (a sidebar maybe) with the past notifications (maybe the last 50?).

After that the most ambitious feature will be to create a post in your blog with your daily activity on the firestatus supported networks. Blogger will be the first to be supported (I use blogger. That 's why :-))

Download here and more info here.

FireStatus meets urlBorg

2008-10-15T12:28:00.001+03:00

The next release (1.2) of FireStatus supports more than TinyURL for url shortening. The new option is urlBorg created by Panagiotis Vryonis a Greek programmer, so we (Greeks as well) felt obliged to add support for his child :-)

The preferences window has been changed to accomodate a new section for url shortening services.For the time, tinyUrl and urlBorg are supported but we plan to add more in the future as well as a fallback mechanism if the selected service fails. Thanks for all the positive comments and don't forget to leave a review :-)

Minor changes ...

2008-10-13T23:27:00.002+03:00

Notice the new items on the sidebar of this blog. Newcomers are the Followers widget which display my only follower and FireStatus co-creator and the Blogs I read. I hope the followers list gets longer over time and the blogs I read gets shorter :-) So if you read this blog add it to your following list and I promise I add yours to mine.

Meet Firestatus

2008-09-29T22:53:00.003+03:00

... a status update utility for multiple social networks. So, what 's this all about? The story goes like this: You see a cool page on the net and you 'd like to share it with your friends or you just want to update your status, the "Good morning, I just woke up" kind of twit. But your friends don't seem to have reached a consensus about THE social network. So, some of them use facebook, some other use twitter, some use friendfeed and you go on and on and on. What do you do to share the cool link with all of your friends (assuming that you have accounts in all of their networks)? You go to each and every social network page and write the same text again and again ? No. You need a client that can communicate with as many networks as possible and send the update to all. I certainly had that need. However the few clients I had seen didn't do the job exactly as I had imagined. My main problem is that even with multi-network clients I have to write the update and send it separately to each network. Why can't I write the text once and send it to all networks with just one click ? It can't be that difficult. Why don't we create such a client as a firefox extension (we are top engineers after all) ? So I discussed the idea with my friends, XUL and Javascript experts, Panagiotis and Dionysios (the best way to solve a problem is to find the people to solve it for you :-)) and here it is. It took us several weeks because we couldn't dedicate much time to the project but in the process we added friendfeed (instead of only twitter and facebook) and Panagiotis added the notification functionality (it 's a good thing to see what your friends are doing on twitter :-). So now we are waiting for your feedback and we are open to suggestions. We plan to add features like the unread notifications list and of course more networks like linkedin, del.icio.us, etc. Every network with a public API is a candidate. And don't forget to leave a (positive :-)) review here.

What I read and liked on 2008-09-23

2008-09-23T11:11:00.001+03:00

Why Isn’t Facebook Making More Money? (Hint: Advertiser Value and User Value Are Not Aligned) - Publishing 2.0
Apart from finding some old friends from high school, I couldn't find any real value to facebook.

What I read and liked on 2008-08-31

2008-09-01T09:31:00.001+03:00

Interoperability Happens - The Never-Ending Debate of Specialist v. Generalist

What I read and liked on 2008-08-14

2008-08-14T14:26:00.000+03:00

Interoperability Happens - From the "You Must Be Trolling for Hits" Department...

Experience vs Knowledge. They both matter. One of the arguments in the article is that applying in production, the brand new language that you just learned, needs acquiring some experience with it first. I have to add that even picking the next language to study will be greatly helped by experience, otherwise you might end up waisting time learning useless things

Interoperability Happens - More Thoughts on Architects and Architecture

Are you a software architect or a software engineer? Someone that
designs a software system takes into account restrictions like budget,
time schedules and dealines, available staff etc. In that sense his job
is not strictly technical but it also has an economics aspect.
Therefore the word "engineering" seems more appropriate. At least, in
my language (Greek) the word architect has an artistic essence while
the engineer is more technical-economics oriented.

What I read and liked on 2008-07-16

2008-07-18T00:35:00.001+03:00

Things I learnt during, and about, my PhD
I couldn't agree more.

What I read and liked on 2008-07-16

2008-07-16T21:39:00.001+03:00

So You Say You Want to Kill XML....
An interesting and more cool-headed approach to the Protocol Buffers open-sourcing

JHUG Java Tech Day 07-06-2008

2008-06-08T21:44:00.001+03:00

I am too lazy to write a detailed report for the event. Anyway, Paris already did it and Dionysios will certainly write about it soon. I just want to once again declare my willingness to give Netbeans a try (and once again I won't find the time to do it :-)) after the Netbeans presentation by Mikhail Kondratyev. The javascript editor, Mercurial support and the project groups (I really miss them in Eclipse) are of particular interest to me.

I will keep one quote from Kirk Pepperdine 's talk and that is:

"Databases cannot scale"

His presentation was very interesting but I have various db issues so this particular quote got stuck in my mind.

The Jbossians gave very vivid and enjoyable talks. Jboss 5 is something that we 've been expecting for quite some time and another feature set presentation just made us even more anxious, so Jboss guys, get it out soon! The event finished with Jboss cache and despite the fact that I haven't used it before, Manik 's presentation managed to keep my interest.

Ok, now that I finally did my lazy man 's report I cannot close without saying a good word about the lunch break that was really great. Hungry developer cannot code (Slightly altered version of a Greek proverb).

What I read and liked on 2008-05-30

2008-06-08T21:11:00.001+03:00

Quality Assurance Driven Development - And The Resulting Damage...
Couldn't agree more...

What I read and liked on 2008-05-29

2008-05-29T19:06:00.001+03:00

Τhe Six Sun Sins
This guy is unbelievable. BTW, I tend to agree with him about JavaFX.

On languages, life etc - Part #2

2008-05-23T12:11:00.003+03:00

This post is actually a comment to the comments at my previous post, but it grew too big so it deserves to be a new post.
So in my previous post, past said:

"Agreed. But that is the wrong question. Very few of our clients ever asked for Java development either. All the client wants is working software that meets his needs. Certainly I, or anyone else that I know for that matter, never asked Facebook to use Erlang for its chat feature."

I 'm glad you agree and you give me the opportunity to explain that my reference to the client 's demand for a specific language had a slightly different meaning. I agree that the client usually does not ask for a particular technology, so if you choose Java or Scala is of little interest to her/him. Do you believe that there exists a language that will do the client 's job 100 times faster or otherwise better? I don't. If my choice of a new language over e.g. Java achieves a performance increase of 0.0001% neither the client will care nor I.

My post was a reaction to the chaos of thousands of programming languages and frameworks that have flooded our professional lives. I agree that the customer usually don't ask for a particular language or framework and it is our responsibility to choose the more suitable solution. Do you believe that in order to achieve that, we should constantly study and improve ourselfs ? I certainly do. Do you believe that ScumbagX#+ is an essential asset for a developer in Greece ? Ok, I again go with you. Do you beleive that we should spend our time deciding between ScumbagX#+, JScumbagX#+ and IronScumbagX#++ because the last one is 0.00001% faster? I certainly don't. What I mean is that every geek in this world dreams of creating his own language that would incorporate all the great concepts that he learned in the "programming languages" course at the university. Am I obliged to learn it ? If I am (and sometimes some new language deserves my time) then I will, but I don't have the illusion that in this life I will manage to learn all of them.

"If you can meet your customers' requirements and be competitive with what you already know, then by all means do so. Working as a developer in most software houses is not that demanding after all."

Everything in this life is a trade off. Our last web app was written in java for jboss. It is an internal application used by 50 users and the type of application that will never go on the public web. If we have written it in Erlang and could manage 50 gazillions requests per millisecond, do you think that the client would have paid us more ? Not in a million years! If we had to write an app that had to deal with 50 gazillions requests per millisecond then ok. Erlang might have been the right choice and the time investment to learn it would be justified.

"However, if you have any aspirations to ever work on a startup like facebook, twitter or friendfeed, or worse, start your own, then you might need to work a wee bit harder than that."

Everything in life is also a bet. If you want to start the new Facebook, you bet on some technologies and invest on them. You cannot do the same for every existing technology. The reason is simple. We won't live for 200 years.

I 'm closing with a clarification for synodinos:

"BTW are you this cautious about all new technologies, because I think you were (somewhat of) an early adopter for JPA?"

JPA was actually one of my early adoptions that caused me absolutely no trouble (I cannot say the same for struts 2 though), so this can be no reason for being cautious about new technologies. Actually, I have to clarify that I am not cautious about new languages. On the contrary, I trust them all. Completely. And I am convinced that each and every one of them was created with good intentions. But you cannot invest on all of them. You have to find a golden rule. I totally agree with those that support the opinion that a developer should know more than one language. On the other hand a developer can go far enough and know TOO many languages but be really good at none of them (I think I read that here :-)).

On languages, life etc

2008-05-22T22:20:00.002+03:00

In a previous post I implied that in Greece it is of no value for a developer to learn Scala. My good friend George commented:

"If your clients are located in Greece, investing in Scala might be totally premature.

(OTOH, this means that I must play with Scala:) )"

George and I and some more of my friends would study Scala just for the fun of it. But that 's all. Fun. I have the extremely strong feeling that no client of ours will ever demand development in Scala. Of course Scala is just an example. The same is true for Erlang, F#, Ruby or Duby or Scuby or any of their variations like JScuby, or Duby# or Scuby++ or DubyScript or Scala on Rails or on a bicycle. Give me a break here, will you ? I just have only one life! Even if I wanted to learn all of them there is not enough time in a person 's life. I don't believe that in this universe there are enough clients that would ask for development in JScubyDuby++##Script that would justify my time investment. Even if I had to leave my company and go to work anywhere else in Greece my knowledge of FRuby#FX wouldn't be much appreciated. But maybe I don't know what I 'm talking about.

What I read and liked on 2008-05-22

2008-05-22T21:59:00.002+03:00

Java Architectural Knowledge for Job Interviews. Are we prepared?
If we have studied the principles and not the specific tools or frameworks then we are definitely prepared not only for the interviews but also for learning quickly and easily any tool or framework. Unfortunately, in Greece many types of schools produce developers that know one specific programming language on one specific IDE and then every problem looks like a nail.

What I read and liked on 2008-05-21

2008-05-22T12:38:00.001+03:00

Groovy or JRuby?
For a developer in a small company in Greece how valuable may be the knowledge of e.g. Scala? I just wonder ...

JHUG Java Day sponsored by Sun Hellas - 7 Ιουνίου 2008.
I will certainly be there!