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Monday, December 21, 2009

iPhone on a Solaris Host

I'm a moderately happy owner of an iPhone and, as I'm usually running Solaris on my systems, I've struggled to find a working solution to connect my handset to an iTunes instance. One of the major drawbacks of the iPhone is that you really need iTunes: whether you want to upgrade it, back it up, or simply transfer the contents you purchased on the Apple stores, you need iTunes to get the job done.

I'm running several virtualized OS on my Solaris guests with Sun xVM VirtualBox, and never managed to make it work because of some limitations of the Solaris USB driver implementation. A couple of days ago, Sun announced the release of xVM VirtualBox 3.1.2 and in the changelog I read the following:
  • Solaris hosts: several USB fixes (including support for Apple iPhone)

I quickly updated my VirtualBox instance, quickly live-upgraded my Solaris Express Nevada build 116 to Nevada build 129 (during the installation, VirtualBox informed me that it needed recent Nevada builds for the USB kernel module to work properly), plugged the iPhone in an USB slot of a Sun Ultra 24 and it worked!

Sun xVM VirtualBox v. 3.1.2 has been released

Sun xVM VirtualBox v. 3.1.2 has been released. This is a minor update and the current changelog is:
  • VMM: fixed SMP stability regression
  • USB: fixed USB related host crashes on 64 bits Windows hosts (#5237)
  • Main: wrong default HWVirtExExclusive value for new VMs (bug #5664)
  • Main: DVD passthrough setting was lost (bug #5681)
  • VBoxManage: iSCSI disks do not support adding a comment (bug #4460)
  • VBoxManage: added missing --cpus and --memory options to OVF --import
  • GUI: fixed VBox URL in update dialog for German and Dutch languages
  • GUI: NLS updates
  • OVF: fixed export of non standard storage controller names (bug #5643)
  • Solaris hosts: several USB fixes (including support for Apple iPhone)
  • Mac OS X hosts: several fixes for the 3D support
  • Mac OS X hosts: re-enabled CMD+Key combinations, even if the Host-Key isn't CMD (bug #5684)
  • Mac OS X hosts: fixed to fast scrolling if the mouse wheel is used inside the guest (bug #5672)
  • Mac OS X hosts: dock & menubar don't disappear in fullscreen when the VM is not running on the primary display (bug #1762)
  • Mac OS X hosts: added an option for enabling "Auto show Dock & Menubar in fullscreen" (bug #5636)
  • Windows host installer: fixed starting VBox with wrong privileges right after installation (bug #4162)
  • Host interface and host-only networking: prevent driver from unloading while a VM is still active (Windows host only)
  • Host-only networking: fixed host-only interface creation (Windows host only) (bug #5708)
  • Virtio-net: don't crash without an attached network
  • Virtio-net: fixed the issue with intermittent network in VM with several virtual CPU cores.
  • NAT: fixed port-forwarding regressions (bug #5666)
  • NAT: fixed crash under certain conditions (bug #5427)
  • NAT: fixed resolving of names containing a slash or underscore when using the host resolver DNS proxy (bug #5698)
  • ATA: fixed sporadic crash when resuming after a VM was forcefully paused (e.g. due to iSCSI target being unavailable)
  • SATA: fixed raw vmdk disks (bug #5724)
  • Linux guests: increased the default memory for Redhat and Fedora guests
  • Linux Guest Additions: fixed installation on RHEL 3.9 guests and on some 64bit guests
  • Linux Guest Additions: prevent SELinux warnings concerning text relocations in (bug #5690)
  • X11 guests: fixed mouse support for some Xorg 1.4 guests (openSUSE 11.0)
  • X11 guests: fixed xorg.conf modification for some older Xorg releases (openSUSE 11.1)
  • Windows guests: fixed some VBoxService shutdown issues
  • Windows guests: fixed VBoxVideo spinlock issues on NT4
  • Windows Guest Additions: fixed uninstallation issues of NT4
  • Shared folders: fixed resolving of symlink target (bug #5631)
  • 2D Video acceleration: delay loading of OpenGL dlls for Windows hosts to avoid GUI crashes on misconfigured systems
  • 2D Video acceleration: fixed issues with video picture not displayed on playback

The changelog claims that support for Apple iPhone has been included for Solaris hosts. If working, that's what I'd been waiting for months!

Tuesday, December 15, 2009

Java Enterprise Edition 6 has been released

The specification for Java Enterprise Edition v. 6 has been released. This major upgrade introduces many new features to ease Web and Enterprise applications development. The list of the technologies included in this release can be view here. Besides upgrades to veteran specifications such as Servlet, JSP and EJB, the Java EE platform introduces:
  • Java API for RESTful Web Services: an annotation-based API to easily convert a POJO and publish its logic as a RESTful web service.
  • Managed Beans 1.0: Java EE containers can now manage ordinary Java classes with few (or no) restrictions (POJOs). Managed bean support lifecycle events, injection and interceptors. Other specification are, such as Web Beans), are built upon managed beans.
  • Contexts and Dependency Injection for Java (Web Beans 1.0): The CDI specification, built upon managed beans, provides the well-known JBoss Seam's Web Beans functionality to the Java EE platform: a sophisticated context and dependency injection model.
  • Bean Validation: An annotation-based API to declare validation constraints on a POJO and a validation API to programmatically validate bean instances.

If you want to start and try this new platform, download the Java EE SDK or download NetBeans, whose version 6.8 integrates Java EE 6 support and Glassfish Enterprise Server 3.0.

Tuesday, December 1, 2009

Selecting the locale for an user with JSTL

In another post, I introduced the basic internationalization capabilities built in JSTL. The algorithm used to choose a suitable locale for an user is a good default choice: without any effort, your web application will show up in the correct locale.

But what if you wanted to let the user choose the locale?

Well, the JSTL Specification lets you establish a locale and a scope: such as page, request, session, application. The first sketch I'd come up with would be something like creating a servlet to enforce the programmatic configuration.

Language selector servlet

This is a servlet service method prototype:

protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
    final String lang = request.getParameter("lang");
    if (isSupported(lang)) {
        Config.set(request.getSession(), Config.FMT_LOCALE, lang);

    request.getRequestDispatcher("/").forward(request, response);

The important call here is Config.set(...): you're telling JSTL to use the specified locale (as a String) and save it in the session scope. This servlet accepts the lang parameter and, if present, uses it to determine if it represents a supported locale (isSupported implementation is omitted). If it is, it uses it as described above. At the end of it all, forwards the user at the web welcome page (if any).


The servlet described above is the first step towards a complete user customization and is just an example of how you can use the JSTL's Config class. Desirable improvements might be:
  • Saving the user servlet in its profile (if the user has been authenticated) so that future sessions will automatically use the user-specified locale.
  • Using a servlet filter instead of a servlet to automatically intercept the lang parameter and leave the web navigation unaffected.

Internationalization using JSTL

The Java EE 5 platform is a powerful enterprise-level server development platform which in my opinion is very productive including to develop small web modules, provided you've got a suitable Application Server or Servlet Container to run it.

As far as it concerns web development and authoring, Java EE 5 has got some great APIs such as servlet's, JSP's and JSF's. The JavaServer Pages Specification (JSR 245) includes JSTL (JavaServer Pages Standard Tag Library, JSR 052), which are JSP standard tag extensions that include internationalization features.

Creating a Resource Bundle

The first thing you ought to do when internationalizing your application is creating resource bundles. Resource bundles are Java Properties file, organized for locales, whose aim is separating string literal according to the locale they're meant for.

Let's suppose you want to use three locales in your application:
  • en_US
  • it_IT
  • es_ES

Create for Java Properties files, one per locale and one as a fallback. The naming scheme is [bundle-name]_[locale].properties, so that you'll end up with:

Some advances Java IDE, such as NetBeans, let you manage properties files with visual tools and perform basic operations, such as adding a locale or filling up the properties, with a fancy GUI.

Filling the Resource Bundles Up

Filling up properties files is pretty easy: such files contain records with this basic structure:


In this case you would translate every key value for the correct locale.

Using a Bundle from a JavaServer Page with a JSTL tag

JSTL lets you easily use resource bundles in a JSP. The first thing you've got to do is declaring that you're going to use the JSTL's fmt tag library:

<%@taglib prefix="fmt" uri="" %>

The next thing is telling the library which bundle you're going to use. Let's suppose you're going to use com.domain.YourBundle:

<fmt:setBundle basename="com.domain.YourBundle" />

The last thing is using the retrieved values where you need them:

<fmt:message key="your.key" />

Determining the user locale

Maybe you're wondering how JSTL determines which is the user locale. JSTL, by default, determines the user locale by examining the headers sent by the browser and applying a best match algorithm. If your preferred language settings show (in this order)
  1. English
  2. Spanish
  3. Italian

the resulting application will show up in English. The JSTL Specification will give you further details about how to establish a default locale for a web application using JSTL.

In another post, I'll show you how I resolved the problem of locale switching for a given user in an application of ours.

Further Readings

Sun xVM VirtualBox v. 3.1.0 has been released

Sun xVM VirtualBox v. 3.1.0 has been released. This is a major update which introduces some brand-new great features such as (change log excerpt):
  • Teleportation (aka live migration); migrate a live VM session from one host to another (see the manual for more information)
  • VM states can now be restored from arbitrary snapshots instead of only the last one, and new snapshots can be taken from other snapshots as well ("branched snapshots"; see the manual for more information)
  • 2D video acceleration for Windows guests; use the host video hardware for overlay stretching and color conversion (see the manual for more information)
  • More flexible storage attachments: CD/DVD drives can be attached to an arbitrary IDE controller, and there can be more than one such drive (the manual for more information)
  • The network attachment type can be changed while a VM is running
  • Complete rewrite of experimental USB support for OpenSolaris hosts making use of the latest USB enhancements in Solaris Nevada 124 and higher
  • Significant performance improvements for PAE and AMD64 guests (VT-x and AMD-V only; normal (non-nested) paging)
  • Experimental support for EFI (Extensible Firmware Interface; see the manual for more information)
  • Support for paravirtualized network adapters (virtio-net; see the manual for more information)

As far as it concerns myself, teleportation is the feature I was looking forward. Great job, guys.

Read the changelog.
Download Sun xVM VirtualBox now.