- c'est finalement Oracle qui va racheter SUN : 7,4 milliards de dollars. Les conditions de pérennités des produits SUN n'étaient pas suffisamment garantit par IBM (beaucoup de doublons). Quelques analyses du web.
- Le programme des sessions de JavaOne 2009 pour début juin 2009 à San Francisco.
- Les EJB 3.1 : la version 3.1 atteind un niveau de maturité suffisant ?
- Un article sur l'inversion de dépendances DIP (à ne pas confondre avec l'injection de dépendance DI, que l'on ne doit pas confondre avec l'inversion de contrôle IOC).
- La configuration de Spring par annotations : simplifier vous la vie.
- un article théorique de Wikipedia sur la covariance et la contravariance et l'invariance : deux notions souvent méconnues que les langages (y comprit Java) propose partiellement. Java propose le return des méthodes covariant : une redéfinition d'une méthode peut déclarer retourner une sous-classe du return de la méthode qu'elle redéfinit. Une méthode peut également déclarer lever une exception d'une sous-classe des exceptions de la méthode qu'elle redéfini. Dans tout les cas, Java reste safe au niveau du typage statique.
Bonne lecture.
Oracle Buys Sun
Oracle Corporation (NASDAQ: ORCL) and Sun Microsystems (NASDAQ: JAVA) announced today they have entered into a definitive agreement under which Oracle will acquire Sun common stock for $9.50 per share in cash. The transaction is valued at approximately $7.4 billion, or $5.6 billion net of Sun's cash and debt. "We expect this acquisition to be accretive to Oracle's earnings by at least 15 cents on a non-GAAP basis in the first full year after closing. We estimate that the acquired business will contribute over $1.5 billion to Oracle's non-GAAP operating profit in the first year, increasing to over $2 billion in the second year. This would make the Sun acquisition more profitable in per share contribution in the first year than we had planned for the acquisitions of BEA, PeopleSoft and Siebel combined," said Oracle President Safra Catz.
"The acquisition of Sun transforms the IT industry, combining best-in-class enterprise software and mission-critical computing systems," said Oracle CEO Larry Ellison. "Oracle will be the only company that can engineer an integrated system – applications to disk – where all the pieces fit and work together so customers do not have to do it themselves. Our customers benefit as their systems integration costs go down while system performance, reliability and security go up."
Oracle rachète Sun
La nouvelle est tombée à la surprise générale : Oracle a racheté Sun.
Malgré les rumeurs persistantes de rachat par IBM qui courraient depuis quelques semaines, c'est bien l'éditeur du célèbre SGBD qui a mis la main sur le convoité créateur de Java. Le rapprochement de ces deux poids lourds du monde J2EE risque d'entrainer de profonds changements dans nos écosystèmes dans les mois à venir.
Oracle Buys Sun - Coverage from around the Web
In what could be the most important decision of the year, after weeks of speculation of IBM buying out Sun, which failed to produce a result, today Oracle have swept in and bought Sun. DZone has assembled a collection of news coverage and 'Tweets' from around the Web (this list will be updated throughout the week -- feel free to post additional links in response to this thread).
What's Going to Happen with OpenOffice, MySQL, SPARC?
With today's surprise announcement that Oracle will acquire Sun Microsystems, several questions were raised as to some Sun products, including MySQL, Solaris, and OpenOffice.org. Browsing around the net, there are several viewpoints on the future of these Sun products, and the OpenOffice.org team has even issued a statement itself.
Let's start with the OpenOffice.org team. They are optimistic about this announcement, and are happy that this marks the end of the uncertainty around Sun's future. "We've been very comfortable with the way that Sun set up the project and has kept a careful eye on us over the years," John McCreesh, OpenOffice.org's marketing lead, told ZDNet, "They'll be a hard act to follow, but we'll approach the future with optimism and an open mind."
A more problematic situation could arise for MySQL. What would Oracle, a company focussed on database products, see in the open source database MySQL? Software engineer Ryan Thiessen, an 11-year MySQL veteran, will be speaking at the MySQL Conference this week, and he wrote a blog post this morning, titled "Stunned".
I am stunned at the news that Oracle is buying Sun. This is not because I fear change or uncertainty, last time this year I was cautiously optimistic about Sun's purchase of MySQL. But not this year, it's fear and disappointment over what this means for MySQL.
When I read this as a rumour a few weeks ago I thought it was a joke of an idea. Why would a high margin software company want to buy a declining hardware business, even if that hardware is great? As for their software, I cannot imagine that Oracle is interested in Java, MySQL, etc as revenue generating products, it would just be a tiny blip for them.
Another line of thinking goes into another direction than Thiessen's. Oracle serves the higher end of the database market, compared to MySQL which focusses on the lower end of the same market. With round and about 11 million installations, MySQL offers Oracle a lot of leverage in a market they previously didn't really took part in. "While no one could ever rightfully claim that MySQL threatens Oracle's higher-end database offerings, its addition to the portfolio gives Oracle additional leverage in a market with significant growth potential," Independent analyst Carmi Levy told BetaNews, "The MySQL installed base of approximately 11 million gives Oracle sales teams fertile opportunity to have conversations they haven't previously had."
Personally, I fear the future of the SPARC platform. SPARC hasn't exactly been doing stellar lately, and has all but vanished from the workstation segment. In the high performance computing market, it isn't doing very well either; in 2002, 101 of the Top 500 supercomputers were SPARC-based - now, that has dropped to just one. Developing and maintaining your own architecture is a costly business, especially in the face of cheap x86 processors.
As a final note, both IBM and Microsoft were surprised by the announcement. "I just learnt it [...] I need to think about it. I am very surprised," Steve Ballmer told Reuters. Apparently, IBM was surprised as well; they were still hoping to buy Sun.
JavaOne 2009 : le programme des sessions
L'annonce du programme des plus grosses conférences du monde Java est toujours intéressante car elle permet d'observer les tendances du moment, du point de vue des organisateurs tout du moins.
Celui de JavaOne 2009 est maintenant connnu. L'observation de ce programme permet de constater que certaines technologies sont particulièrement mises en avant :
- JavaFX : incontestablement le sujet majeur de ce JavaOne, faisant de cette conférence le bras armé de Sun pour la mise en oeuvre de sa très agressive stratégie marketing. En effet tous types de sessions confondus (BOFs, conférences techniques, Hands on, …), on compte pas moins de 40 sessions dédiées à JavaFX sur les 350 que comptera au total cette édition de JavaOne.
- JEE 6 et JDK7 : assez logiquement, du fait de leur planning de finalisation, ces deux technologies sont très présentes grâce à des sessions dédiées à chacune de leurs composantes.
- Rest et Cloud Computing : en terme d'évolution de l'architectures des applications, le Cloud Computing et Rest sont les deux concepts qui semblent destinés à marquer le plus l'année 2009 et JavaOne s'en fera donc l'écho.
- Complex Event Processing : cette technologie, consistant à analyser les évènements d'une EDA, n'est pas nouvelle, il en est question depuis plus de 5 ans. Toutefois elle connaît un nouvel essor depuis peu. Après avoir fait une apparition lors de Devoxx en décembre dernier, c'est maintenant JavaOne qui va lui consacrer 4 sessions contre aucune lors de sa précédente édition.
EJB 3.1
Enterprise Java Beans (EJB) is a server-side component architecture for the Java Enterprise Edition (Java EE) platform, aiming to enable rapid and simplified development for distributed, transactional, secure and portable applications :
- No-Interface View
- Singleton
- Asynchronous Invocations
- Global JNDI names
- Timer-Service
- EJB Lite
- Simplified EJB Packaging
- Embeddable EJB Containers
- Best of the Rest
- Conclusions
Examining the Dependency Inversion Principle
The Dependency Inversion Principle is defined as follows:
- A. High-level modules should not depend upon low-level modules. Both should depend upon abstractions.
- B. Abstractions should not depend upon details. Details should depend upon abstractions.
Conclusion
The Dependency Inversion Principle sets forth a design strategy for allowing higher-level modules to be easily reused by reversing conventional dependency relationships, though at times dispensing with the ability to reuse equally valuable lower-level modules. While lacking the notion of dependency inversion, a combination of the Separated Interface pattern with the Adapter pattern can be leveraged to achieve the same design goals without the negative consequences of coupling lower-level components unnecessarily. Nevertheless, the strategy set forth by the Dependency Inversion Principle offers a good intermediate level approach for decoupling the higher-valued components within an application.
Spring Annotations
Depuis ses débuts, le moyen le plus courant de configurer Spring a été basé sur XML.
Mais comme les développeurs sont apparemment lassés de naviguer sans fin à travers un dédale de crochets, des utilisateurs ont commencé à chercher d'autres moyens pour connecter leurs beans dans leurs applications basées sur Spring.
Spring a répondu avec des options de configuration basées sur les annotations.
Dans cette carte de référence, vous trouverez un guide à l'ensemble des annotations proposé par Spring 2.5.
Covariance and contravariance (computer science)
From Wikipedia, the free encyclopedia
Aucun commentaire:
Enregistrer un commentaire