Null Pointer exception when adding content to DSpace

The Problem

My coworker and I were installing a fresh setup of DSpace on an existing Oracle 10g installation. First of all, deploying the application via the Oracle Application Server was not working at all. Eventually we decided to make an exception for DSpace (from our normal deployment procedures in my office). We set up Apache Tomcat on RedHat Enterprise Linux 5 and the application finally deployed.

We started testing the application and things looked fine. Very soon we realized that when we tried to add content to DSpace, the content creation process was not functioning properly. Null values were being passed through the content creation process, and content could not be saved to the database due to Null Pointer Exceptions.

We searced all of DSpace's documentation, Googled, re-Googled, and Googled the terms again looking for what could be throwing the error.

Installing .docx support in in Linux

Update: Beginning with 3.0, reading and writing Microsoft Office 2007 file formats is now supported out-of-box and this guide is no longer relevant.

Microsoft Office 2007, another member of the crappy Microsoft product family, has graced us with the .docx format. It's the "open xml format" which no one else can seem to use. There's an interesting article here,, about the difficulty for other vendors to implement Microsoft's "open" standard. I'm no expert at examining document standards, but the article is convincing and we all know Microsoft's history. 

Hibernate 3 antlr.jar conflicts with OC4J's TopLink antlr.jar

The Problem

I'll say it here and I'll probably say it again -- I hate Hibernate. Nonetheless, several of the applications in my office implement the technology and we can't take it all out all at once. We deploy to an Oracle Application server and develop locally using Eclipse and OC4J.

One particular feature of Hibernate is HQL (Hibernate Query Language) which is for writing object-oriented SQL queries. One of my applications kept throwing errors with regard to Hibernate HQL-related sections. One error in particular that kept coming up was:

org.hibernate.QueryException: ClassNotFoundException: org.hibernate.hql.ast.HqlToken 

The errors were being thrown on my local OC4J server and our office's Oracle Application Server but not on my local Tomcat server. What could be the cause?

How to parse a query string using Javascript

So at my job, our Google Appliance server needed a reboot, and was going to run fsck on its next startup. This would take anywhere from 5 minutes to 6 hours. So I had to write a quick script to live in the Google Appliance server's spot during this outage which would redirect all searches to Google and put in the text ''.

There was a great article on how to parse query variables from a URL over at a blog called Idealog.

Hello World

Hello world!

OK... good this thing works :) My name is Reid and I will be your host for your time at this website. This is my first post... by far the least interesting. To get to know a little bit about my blog check out the About section.


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