Develper’s Diary

Title: “The developers’ diary …”

“Interesting, unusual, funny, intriguing stories from the programmer’s daily work” – stories, funny pictures, experiences from various stages of software production. A strange conflict in the team? Examples of misunderstanding customer requirements? Problems in communication? A morning discovery, that code written late at night was flawed and you could have written it more efficiently.

Despite the fact we are not stand-up comedians the life, itself brings us many interesting situations and stories worth telling. Any such story is a good lesson what can go wrong, where we can be surprised.

That’s why we invite you to a mini-competition for stories related to the programmers work. What are the rules?

  • Step 1 : Write down your story, prepare it for publication and send it to our address This might be a short story, an anecdote, a picture or mini topic submission *

  • Step 2 : All entries will be published on the conference webpage on “the developers’ diary” tab**.

    First part of the contest runs until October 20th. After this date, we will choose and reward 2 stories with gadgets and prizes and all the participants will receive a special discount code.

    However this is not the end …

  • * Step 3 (optional) : During the conference, one of the lectures will be intended for the panel, during which you can show a short, 5 minute presentation of your story. If you have a light, funny stories and want to practice public speeches, here is a possibility.

  • Step 4 : During the conference, participants will take part in voting to select the story they liked the most. The winner will receive a PSP console while we will award the best stories with books.

* Step 3 is optional

** Program Council reserves the right to select and censor the applications:)

If you have questions please contact organizers .

Story 1 by Sławek Sobótka

Tytuł: java.util.Calendar and the Polish issue: where are my 24 minutes?

*Problem:*

We had a large system in which applets were used as server’s clients. In many forms it is possible to edit the time of certain events. Time is usually edited in a text field in the format of hours:minutes. Unfortunately, in some forms we can observe the following condition: if we enter a time, save, then we re-edit the record, time is always set back by 24 minutes! The number 24 is associated to everyone with the number of hours in each day so it is a perfectly deceptive value …

*Technical Background:*

Time in programming, for reasons that only the ancestors from the silicon bronze age remember, was recorded in the database as:
01/01/1900 hour_from_form: minute_from_form:00000

The key here is the first of January 1900.

Saving and loading worked properly. Communication between applet and server services via Spring Remoting (remote Bean method calls in Spring, parameter serialization and the results and exceptions) was fine.
Time was sent in DTOs as objects of class java.util.Calendar (used more or less to manipulate time) instead of java.util.Date (used as a container for the time).
Calendar is such a clever class of objects that it explores the location of the operating system on which they live. In the case of signed applets they did so on the client machines after their transmission and deserialization.

* Good to know: *

After a week of searching it turned out that deep in the code there is a calendar logic that takes into account the following fact: on 4th August 1915 on Polish territory there has been a standardization of time, so as to fit the global time zones, and then the watches were shifted for about 24 minutes:)

(unfortunately) Gentlemen from Sun did their history lessons …

Story 2 by Damian Nowak (AtlasHost.eu)

“My biggest coding-fail”

403 Forbidden

fail code

Do you already see the bug? Fortunately, it didn’t go to production – thanks to “code review” that is actively practised in my company (Spartez).

Why don’t you practise code review in your team? You don’t know what it is? It’s high time you googled and started using it!

Spoiler: First modify and save page content, then check the permissions. If user is not permitted, reply 403 Forbidden. Oh wait, the page is already modified. ;-)



  • jdd

Organizer:

Gold Sponsors:

  • e-point
  • j-labs

Silver Sponsors:

  • Lumesse
  • Luxoft
  • SII

Sponsors:

  • Redhat
  • WITS

Sponsor JDD Afterparty:

  • WITS

Media Partners:

  • helion
  • Polish JUG
  • Poznan JUG
  • SDJ