JavaDay in Turin, October 20th

On its second edition, the Javaday is an initiative organized by the Italian Java User Groups, by the community of Java Italian Portal and by the Java Italian Association with the goal to promote the knowledge and the usage of the Java technology. JavaDay is an on road gig that touches different italian cities all along the peninsula, spreading the Java technology also in places usually skipped out by big events. This feature makes the JavaDay a qualifying and unique moment: every single stage is a direct communication channel in which the technology, the local institutions, the developers and the companies can meet together in order to know each other, share knowledge, compare each other and understand the new opportunities offered by the Java Platform. The participation to the JavaDay is free.

http://javaday.jugtorino.it

Live from Sun Tech Days

Hi, blogging live from Sun Tech Days here Milan! People is coming, and the place is getting crowded The first person I met was Roman Strobl, who’s still setting up his demos for today. Unfortunately I’ll be able to stay only this morning, but I’ll do my best to get the most from the event, even if I’ll be stuck at JUG desk.

JUG Torino September’s meeting!

September’s meeting of Java User Group Torino will take place on 21h with this schedule:

• 18.30: Check-in!
• 18.45: Quickie: “What about Hudson?“ by Bruno Bossola (JUG Torino)
• 19.00: Seminar: “GWT, a Web2.0 toolkit!“ by GianCarlo Pace (JUG Milano)
• 20.00: EOF (as usual, maybe having a VeryBigPizza all together!)

You may find more info about the event here.

Invoking an Ant task using a specific JVM

Sometimes you’d like to invoke Ant using a specific JVM, maybe because you want to compile using a well specified JDK implementation.

I solved this problem with a task like this:

<macrodef name="ant-jvm">

   <attribute name="target" />
   <attribute name="jvm" />
   <attribute name="antfile" default="build.xml"/>
   <attribute name="basedir" default="."/>
   <attribute name="args" default="-Dsample.value=xxx"/>
   <attribute name="taskname" default="ant"/>

   <sequential>

      <java classname="org.apache.tools.ant.launch.Launcher"
            fork="true"
            jvm="@{jvm}"
            failonerror="true"
            dir="@{basedir}"
            timeout="99999999"
            taskname="@{taskname}">

        <classpath>
            <pathelement location="${ant.home}/lib/ant-launcher.jar"/>
        </classpath>

        <arg value="-buildfile"/>
        <arg file="@{antfile}"/>
        <arg value="@{args}"/>
        <arg value="@{target}"/>
        <arg value="-Dbasedir=@{basedir}"/>
      </java>

    </sequential>

</macrodef>

You may use it instead of <ant> task and allows you to specify the jvm to use, something like this:

    <ant-jvm target="-do-ejbdoclet" jvm="${java-1.3}/bin/java" />

Quick and dirty, but it works

A usecase is an object.

It seems naive, doesn’t it? It seems to be that sort of thing that everyone know, right? Well, get into your code and, please, find the object representing a usecase. You didn’t find it, did you? Object Oriented is far away from being adopted, neither understood.

In these days I’m working on some code developed by one my fellow colleague, who’s absolutely a master in technology: he knows the very everything about each framework, tool and library… such a cool boy to work with! But it lacks OO, he always thinks in term of “how” and never of “what”, and its code is always “code”.

In my opinion, each usecase should be present in form of an object into your code, every system interaction should be present in form of a method exposed by the usecase object, the state of your system is the state of the usecase object. And, yes, this is not enogh, more to come. But start thinking about this, please, before switching to the next framework or tecnique. Please do business logic.

Jazoon 07

Here we are! Live at Jazoon07!

Quite impressive stuff! I found it to be a professional conference, as expected, and it was possibe to meet many interesting people, Neal Gafter among the others (nice pictue of Neal on JUG Milano website, where he’s managing large amounts of swiss food! )

Here I summarize my impressions, given that I completely agree about what Filippo and Roman already wrote

Pro’s:

• large amount of speeches to choose from. every day
• many PC and printers available to public
• free traveling ticket for public transport was a great idea
• free Toblerone was beautiful (but please, don’t wait the very last day to release it!!!)

Con’s:

• notepad and pen missing from welcome bag
• bad conference map, with speeches’ abstract collapsed in four lines, the first four (men, you asked as for five pages! So what?)
• no java-champions BOF (but this was also our fault )
• official jazoon blog is not very up-to-date

Anyway, I definitely recommend this conference!

And yes, my speech went very well :), you may also take a look at a more complete report on JUG Torino website (unfortunately, it was written in Italian)

March’s meeting of Java User Group Torino will take place on 15th with this schedule:

• 18.30: Check-in!
• 18.45: Quickie: “UML for dummies!” by Bruno Bossola (JUG Torino)
• 19.00: Seminar: “Design Patterns by examples: Decorator“ by Domenico Ventura (JUG Torino)
• 20.00: EOF (as usual, maybe having a VeryBigPizza all together!)

You may find more info about the event here.

JavaPolis 2YK6

JavaPolis is at the end, the last session is running now and people are leaving the site. What an event! I met a bunch of people I would never imagine to met, like Kirk Pepperdine, David Booth, Bruno Souza, many evangeist from Sun and many, many more!

I had my speech this morning, and all went well… yeah, it was great! A big room, crowded of interested and, strangely, awake people! (it was 9.30 in the morning :-D)

So…. what more can I say? So much fun, everithing was almost perfect, nice food (and note, I’m an italian guy :D), better if you plan to come next year!!! More will come, now I must leave to come back… see you soon!

JavaDay in Rome!

On 2 December I was speaker at JavaDay in Rome… it was great! Rooms were crowded, the conference was very interesting, food was fantastic and Rome is always a beautiful city A great “thank you” to JUG Rome, JIP, JIAfor organizing such great event.

You may find slides of my speech here

When like is not what you like

I’ve been always using PreparedStatement in JDBC query operations for two main reasons:

• it manages for you all data translations between types
• it automatically calculates the best query path to recover your data

Unfortunately there’s a little canvas you should know about: we know, like is evil, but when you use like in a query using a PreparedStatement, data path is calculated before having information about what you would like, so resulting query is very unoptimized! In such cases you should proceed handling like parameters with string composition/substitution, before creating PreparedStatement object.

That’s not a JDBC or database fault, it’s just how things work. But you should be aware of it…