Singleton Design Pattern in Java

Dec 3, 2008 · 1 min read

·

Il design pattern Singleton è il primo design pattern in cui si si imbatte, ed è molto importante anche perché aiuta a comprendere meglio i linguaggi OOP.

Potete trovare un’ottima introduzione presso Wikipedia, dove leggiamo:

Il metodo più semplice per implementare questo pattern è quello di rendere privato il costruttore della classe impedendone così l'istanziazione diretta, e nello stesso tempo fornire un metodo getter statico che restituisca ogni volta la stessa, unica, istanza

Ecco un esempio in Java:

public class MioSingolo {
    private static MioSingolo istanza = null;
private MioSingolo() {}

public static MioSingolo getMioSingolo() {
    if (istanza == null) {
        istanza = new MioSingolo();
    }
    return istanza;
}

}

Ecco lo stesso esempio thread safe…

WordPress 2.7 Release Candidate 1

Dec 2, 2008 · 1 min read

en software · development wordpress

·

Share on:

After some time, Wordpress 2.7 is out:

WordPress 2.7 Release Candidate 1
By Ryan Boren. Filed under Releases.

With the release of RC1, we’re in the final leg of development before the release of 2.7. 280 commits since beta 3 have polished the new admin UI (including new menu icons created by the winners of our icon design contest) and fixed all known blocker bugs.

Read More

Drupal, Wordpress & Joomla

Dec 1, 2008 · 3 min read

it · fareimpresa informatica

·

Share on:

La scelta di un Content Management System (CMS) è spesso cruciale, soprattutto se dovete usarlo per creare un sito per un utente finale poco smaliziato.

Vi sono così tanti software di CMS, che scriverne uno da zero è quasi sempre un’opzione da considerare con molta cautela.

In questo articolo prenderemo in esame tre CMS scritti in PHP, molto diffusi e con un nutrito numero di fan.

Log Manager

Nov 28, 2008 · 1 min read

it software · design example formazione java

·

Share on:

Il seguente esercizio operativo serve per prendere confidenza con:

Libreria Java Servlets & JSP
Libreria Log4J

Si richiede di creare una pagina jsp che consenta di modificare dinamicamente alcuni livelli di logging:

Dettagli:

Si richiedono 5 livelli di log (qui ne sono mostrati solo 3 per semplicità)
Si richiede di poterli configurare modificando un solo punto (es 5 var nascoste nel form)
Si richiede di poter configurare la password (idem come sopra)
Se la password è errata il sistema registra su un log l'errore e non fa nulla, ripresentando la maschera.

Riferimenti

Specifica HTML: FORMS

Worldometers - real time world statistics

Nov 27, 2008 · 1 min read

en · relax world

·

Share on:

On Friday, at Gioorgi.com we look for interesting sites to give you a shot.

Whe have found this site, “managed by an international team of developers, researchers, and volunteers with the goal of making world statistics available in a thought-provoking and time relevant format to a wide audience around the world”.

Bug Tracking Tools 3: Trac

Nov 26, 2008 · 1 min read

en knowledgebase software · bugtracking development

·

Share on:

Trac is a quite famous bug tracking software written in python.

It is considered very strong its subversion integration

Pros: Can Also work with an embedded database (using sqlite). Easy to setup and use.

Cons: Feature are too much, and aims to be also a CMS to some extend.

I dati della crisi

Nov 24, 2008 · 2 min read

it · crisi economia

·

Share on:

In un articolo del corriere della sera del 19 novembre 2008, leggiamo un inciso che dà un’idea della crisi in atto. Si riporta una discorso del ministro del Tesoro Henry Paulson (grassetto nostro):

Paulson [...] ha spiegato che, anche se la crisi rimane grave, non è cosa da poco che il sistema sia sopravvissuto a una spaventosa distruzione di ricchezza. Ed ha fornito un dato impressionante: le istituzioni che nei mesi scorsi «sono fallite o hanno vissuto una situazione che equivale a un fallimento», e cioè Bear Stearns, IndyMac, Lehman Brothers, Washington Mutual, Wachovia, Fannie Mae, Freddie Mac e il colosso assicurativo Aig, all' inizio del 2008 avevano un patrimonio complessivo di 4,7 trilioni di dollari: una cifra pari a due volte e mezzo il Prodotto interni lordo dell' Italia. Una ricchezza andata quasi completamente in fumo.

Che sia semplice!

Nov 23, 2008 · 2 min read

it software · design economia fareimpresa formazione

·

Share on:

A Gioorgi.com VIC 20 Boot Screen ci occupiamo di software da molto tempo. Giovanni Giorgi respira il software dalla metà degli anni ottanta, quando il Vic 20 fu commercializzato in Italia (abbiamo trovato molti dettagli sul nome e la storia del VIC-20, ma la fonte più attendibili è sempre wikipedia).

Dopo così tanto tempo, possiamo affermare uno dei principi fondamentali che qualsiasi persona si occupi di software deve tenere a mente.

Non importa se siete account, ingegneri, responsabili di marketing o semplici sviluppatori junior. Dovete sempre tenere a mente che il software che producete deve essere facile.

Commodore BASIC as a Scripting Language Open Source

Nov 20, 2008 · 1 min read

en · relax basicV2

·

Share on:

Commodore BASIC as a Scripting Language for UNIX and Windows - now Open Source:

Here is a little background:
This application is a recompiled version of the original Commodore 64 binary - it is not a reimplementation, so while it runs at pretty much the maximum possible speed, it is still 100% compatible. The huge C file in the archive has been produced by feeding the original 6502 code into my static recompiler and optimizing it with LLVM. The original operating system interface (character I/O, LOAD, SAVE etc.) has been reimplemented in native C, so Commodore BASIC interfaces nicely with OS X/Windows/Unix - you can use pipe I/O, and you can pass the filename of a BASIC program on the command line.

Read More

Bug Tracking Tools 2: FogBugz

Nov 19, 2008 · 4 min read

en knowledgebase software · bugtracking development

·

Share on:

As we have seen, bug tracking tools are a very important piece of your It infrastructure. Some tools aims to be a storing ticketing system (like Remedy), others a simple bug tracking tool. In this second post we are going to analyze one of them, called FogBugz

Django 1.0.2 is out

Nov 19, 2008 · 1 min read

en software · django news python

·

Share on:

We read and report:

Tonight, to clear up some problems with the packaging of the Django 1.0.1 release from Friday, we've released Django 1.0.2; once again, this is a bugfix-only release, and is a recommended upgrade for anyone targeting or using Django 1.0 or Django 1.0.1.
Weblog entry announcing the release is here: http://www.djangoproject.com/weblog/2008/nov/18/102/ Release notes are here: http://docs.djangoproject.com/en/dev/releases/1.0.2/

Selling software which is of some value

Nov 16, 2008 · 3 min read

en software · opensource redscorpion

·

Share on:

At Gioorgi.com, after working with a lot with software for over twenty years, we have envisioned a clear idea about open source. This is the second article of a series tagged “opensource”: the previous one is Open Source for the infrastructure; in such article we started to do some tiny consideration of the destiny of big closed huge framework. Things are getting bigger and bigger, and maintaining big code library is a high cost for software house

In the 2008, when I look at software I ask only a thing: to be simple. Embarrassingly simple. The success of Mac stuff (like ipods, macosx and so on) is based vastly on simple design of ready to use, not annoying stuff.

For this reason, the software is not anymore the focus. Core software should be open source: things like word process are not the future of the business. Things like FaceBook are the future of business.

What you try to sell is your GUI design experience (see things like FogBugz or Wordpress), your networking idea (like Facebook), your focus on search agents (like Google, because too much information is useless by definition).

The new Gioorgi.com

Nov 16, 2008 · 1 min read

en · gioorgi site

·

Share on:

We are happy to publish a Chief Editor Direct Note (CEDìN):

Dear readers, our spirit is strong, as our commitment, to deliver to you the better and best article out of there. For this reason, we had worked hard to do the first major revision of the Site. Here the major changes:

New look, featuring context-pages. Pages are different based on sections. The complete look will rollout in the next month. So keep in touch.

Ajax power: article are loaded via a tiny ajax magic, to reduce site load

The new "Friday relaxing news", for giving you something to read about.

A new set of article about software business, the first of them is already out.

As usual, your comments are always welcome: keep following us.

Giovanni Giorgi, Chief Editor of Gioorgi.com

Soundsnap.com: Find and Share Free Sound Effects and Loops

Nov 13, 2008 · 1 min read

en · business relax

·

Share on:

Soundsnap.com: Find and Share Free Sound Effects and Loops

SoundSnap is a very nice site, you can use to download free sounds to build podcasts and so on. Quality is good, and the interface is fast.

This is our Friday relaxing news! Short stories for the weekend! To get the complete list, please look at the relax tag.

Mantis bug tracking tool 1

Nov 12, 2008 · 2 min read

en knowledgebase software · bugtracking development opensource

·

Share on:

In the previous article we introduced the reader to the bug tracking tools.

In this article we will analyze Mantis, an open source bug tracking tool It is very important to stress you are going to use much more time to set up an open source bug tracking tool. A fraction of this time is for setting it up, but the vast majority of your time will be spent setting it up, customizing it and recovering information on it.