Animated side-scrolling display and tray icon.

The latest version of the ResNet Quota Monitor is still under works, but development is slow since I’m not staying on campus residence and thus allocate a lot less time to it than I used to. That being said, I’m considering to open this project up for others to contribute, so stay tuned…

This new version removes the “balloon” notification, in favour of a slidey toaster/growler that will have a standard look and feel across Windows, OS X and the various flavours of Java-compatible Linux. Here’s a sneak peak – with some icon work by Vince from www.3ntrance.com .

Structually, the system is being re-done, with use of a more intuitive blackboard design pattern revolving around a built-in plug-in manager, for future plug-ins written by the community. It should be robust enough to be extrapolated for other colleges, or just as an application framework for any multi-component project.

And remember, if you ever have UBC ResNet, wireless, VPN, or even Campus Wide Login (CWL) problems, remember to visit the friendly staff at the UBC IT Help Desk.

You most likely have come across the following “warning” level log entry in your Google App Engine logs if you’ve been using Sun’s jersey-core 1.0.x jar and the Google App Engine 1.2.6 SDK:

com.sun.jersey.core.spi.component.ProviderFactory __getComponentProvider: The provider class, class com.sun.jersey.core.impl.provider.entity.XMLListElementProvider$App, could not be instantiated. Processing will continue but the class will not be utilized
java.lang.SecurityException: Unable to get members for class com.sun.jersey.core.impl.provider.entity.XMLListElementProvider$App
at com.google.appengine.runtime.Request.process-819e5bfbf2e72052(Request.java)
at java.lang.Class.getMethods(Class.java:180)
at com.sun.jersey.core.reflection.MethodList.<init>(MethodList.java:57)
at com.sun.jersey.core.spi.component.ComponentConstructor.getPostConstructMethod(ComponentConstructor.java:121)
at com.sun.jersey.core.spi.component.ComponentConstructor.<init>(ComponentConstructor.java:115)
at com.sun.jersey.core.spi.component.ProviderFactory.__getComponentProvider(ProviderFactory.java:158)
at com.sun.jersey.core.spi.component.ProviderFactory.getComponentProvider(ProviderFactory.java:130)
at com.sun.jersey.core.spi.component.ProviderServices.getComponent(ProviderServices.java:190)
at com.sun.jersey.core.spi.component.ProviderServices.getProvidersAndServices(ProviderServices.java:120)
at com.sun.jersey.core.spi.factory.MessageBodyFactory.getProviderMap(MessageBodyFactory.java:136)
at com.sun.jersey.core.spi.factory.MessageBodyFactory.initReaders(MessageBodyFactory.java:110)
at com.sun.jersey.core.spi.factory.MessageBodyFactory.init(MessageBodyFactory.java:105)
at com.sun.jersey.api.client.Client.<init>(Client.java:257)
at com.sun.jersey.api.client.Client.<init>(Client.java:133)
at com.sun.jersey.api.client.Client.create(Client.java:444)
at com.socialjava.TinyFBClient.<init>(TinyFBClient.java:42)
at com.socialjava.TinyFBClient.<init>(TinyFBClient.java:47)
at com.socialjava.TinyFBClient.<init>(TinyFBClient.java:58)

A broken jar.

… and so on, for a lot longer.

In my case, this was due to the Jersey implementation that goes along side Social Java’s Tiny Facebook Client. The App engine admin panel reports that these exceptions are using up a lot of cpu time per request, which is never a good thing. Here’s how to silence them.

 

 

So a recent update to the Google App Engine SDK broke my JSF 2.0 web application. I received this message on local server start-up:

WARNING: Error starting handlers
Throwable occurred: java.lang.NoClassDefFoundError:
javax.naming.InitialContext is a restricted class. Please see the Google
App Engine developer’s guide for more details.

Apparently this was due to how JSF checks if it can use InitialContext first  (bug report)- by invoking it. Unfortunately, this sends GAE into a panic, since javax.naming.InitialContext is not one of the whitelisted JRE classes.

**Edit 3: for your convenience, I have pre-packaged this solution into its own .jar file. See bottom of post for further details.

If any UBC students are on campus October 1st, Microsoft would like to invite you to join them at a “Meet the Company” info session in the Forest Sciences centre.

 

More information:
https://careers.microsoft.com/careers/en/us/collegehome.aspx

Location: FSC 1005
http://www.maps.ubc.ca/PROD/index_detail.php?show=y,n,n,n,n,y&bldg2Search=n&locat1=353

Well I told myself I’d regularly keep a log of what’s going on in my tech life – and clearly that hasn’t been happening. Basically due to the school term and a web prototype called GISH-N (Georeference Information System for Horticulture and Nature (a good use of acronyms)) which finally had given me a cause to try out CodeIgniter.

As I close up my books for the beginnings of summer, I plan to open up my laptop and bring you:

• Team Development and CodeIgniter – 6 people, four months, and countless hours of code
• ResNet Quota Monitor for UBC, v2 – meaner, cleaner, and slicker than before – will be available for Windows/Mac/Linux!
• Distributed Computing Framework – working on a system to easily make your Java App rise into the clouds
• Source Version Control – could  Mercurial be replacing SVN in my future?
  Can’t wait to learn about it? See the Google Tech Talk here:
  Props to Nathaniel for bringing this up

See you in the near future!

Now usually I don’t mind snow, but there are certain types you’ll surely recognize that are just plain annoying. The following is my top three.

3. Slush: these little heaps of snow end up mixing with mud and other flavors of crud. You might consider to go outside, but prepare to get wet.

2. Ice: you’ll be taking baby steps as you strategically get from point A to B. You might as well be traversing a minefield, but you’ll get to where you want to go eventually.

CodeIgniter is a powerful object-oriented PHP framework that Nathaniel introduced me too. It saves a lot of time and pain by structuring your PHP-based application in a logical way while providing you the tools you need to easily render forms, safely access databases, and much more with minimal code. It also utilizes the popular Model-View-Controller (MVC) design, commonly seen in Java Enterprise and ASP.

Trademark of CodeIgniter

Unfortunately, CodeIgniter may not run nicely with certain configurations of PHP and non-Apache web servers due to the handling of the PATH_INFO variable (common diagnosis is only being able to hit your index page, no matter what the URL is). The following sets up PHP and Abyss Web Server to handle this issue.

First of all I’d like to state that this blog hasn’t been abandoned – I’ve just been overwhelmed recently with assignments, school projects and finals. It’s also introduced me to developing rich client applications/plug-ins on the Eclipse framework (see these tutorials from Eclipsecon 2005, old, but still very relevant) and sparked some interest in AspectJ and aspect-oriented programming.

Trademark of the Eclipse Foundation

For those of you that aren’t familiar with Eclipse, it’s well known as a Java-based development environment for software development after starting as a project within IBM. WIth Eclipse’s RCP and plug-in development tools, you can develop and deploy your own application on top of the Eclipse application framework.

Left, the Eclipse Java Development Environment developing a rich client application; right, the rich client application running the Eclipse framework

As for current projects; the ResNet Quota Monitor has since been revived with a revamp to the UI and feature improvements. Also, I’m putting together a prototype for a Helpdesk agent assistant environment called the “IT Help Desker”. More on that and many other techy tidbits in the weeks to come!

It’s common to just take it out of the box, hook it into your network, and never touch it again. Remember that routers are miniature computers too! If you have the right hardware and a bit of spare time, you can make these little boxes do more than just share your Internet connection.

Unlocking your router's potential - not like this.

Some common uses include:

• increase signal strength above factory settings
• managing your network from the Internet
• synchronizing a dynaminc dns address
• additional layer of firewall protection and parental control
• turn on your computers remotely
• using it to access a wireless network/increase its range

Interested? There are countless other uses as well.  But how are these features possible, and why aren’t they all available when you buy your router?

Ever wondered how to connect to your home computer from the office, school, or anywhere with an Internet connection? It’s possible, and that’s through a service called dynamic DNS.

Why would you want to have your home computer available on the Internet?

• a web server to share a website or downloadable files
• an ftp server for users (by account or anonymously) to upload and download files
• remotely control your desktop via VNC from another computer, or iPhone/iPod touch
• SSH in to launch X Window-based applications remotely (see my previoius post about this)

Of course, you restrict what your visitor can access using a firewall or router, so that the rest of the files on your computer and computers on the network are safe (you should be doing this anyways!)

xkcd - Map of the Internet

So what’s wrong with finding out your IP address ( example, by http://whatismyipaddress.com/ ) and using this?

• not very friendly for public use (http://72.233.2.54/, compared to a URL, like http://javadocs.wordpress.com)
• subject to change, as controlled by your Internet Service Provider