Ubuntu won’t boot raided root
Well, I've had a lot of trouble switching my system from LVM, to RAID1+LVM on ubuntu 10.04. I got another drive for my system, created a mirror with one drive (temporarily of course) asked lvm to move my entire system over to that physical device, added the previous drive to the raid array, and rebooted (oops). I am listing a few things that are important to know when you're both new to Ubuntu, and doing raid post installation of Ubuntu.
Removing spaces from filenames
If you use bash under unix, Linux, or Mac OS X, and you're continually forgetting how to convert filenames with spaces to filenames without spaces, then look no further.
ZK AJAX and EJB 3
I went through some issues with EJB3 and ZK. I was using openejb at the time, integrated with tomcat 6. I found that my methods that had role restrictions (using @RolesAllowed) were not accessible. Whenever I clicked a button, an event would be fired, but I would get an error of "Unauthorized Access by Principal Denied", to that method, with a stack trace.
What is JAXB and JAXB Example Code
I thought it may be nice for those googlers that want to know about JAXB, to have a quick working example to use. So, that is the purpose of this post.
ZK AJAX Status Bar
Seeing that my research project is a mini accounting system, I thought it necessary to be able to display items in a status bar, like a real application. It is very slightly unfortunate that ZK doesn't have something integrated right in for this purpose. But, given the versatility of ZK, it's easy enough to resolve.
ZK Exception Handling and Error Popup
Once I had some basic functionality in my mini accounting system that I'm writing (for research purposes), one of my goals was to have an adequate error display for the user, that was the same every time. Suffice it to say, I was completely thrilled to find out that ZK could do exactly what I wanted to do, and I didn't have to write an once of code. All I did was write some ZUL, which wrapped a JSP inside of a ZK window. I share how I did that in this post.
ZK AJAX Framework Introduction
I am in the process of working with and researching ZK as an AJAX framework to integrate into Java Web Development that I do. So far, AJAX looks really amazing, and is fully integrated into the J2EE framework. It is an event driven framework that has the option of hooking directly into existing JSP, or entirely writing ZK event handlers to do the processing. There is no wonder that ZK won the Project of the Month Source Forge award.
RMI Pitfalls and Problems
In this post, I plan on laying out multiple common problems with RMI, that a developer can run into. I hope that this will be a concise guide to fixing the common RMI problems that beginners run into. As I come up with more, I will edit this post, rather than creating a new one. I will then post a comment on this entry; if you are subscribed to the comments (RSS feed), you will get notification when there is an update.
Also, if you are having some sort of RMI trouble, post a comment, and I will let you know if I know the solution. I may also add the solution directly to this post, if it happens to actually be an RMI related issue.
EJB3 @RolesAllowed, annotation type not applicable to this kind of declaration
I'm just learning EJB3, and I'm stumbling here and there. When developing an EJB object, I had a problem where the compiler was giving me an error that says "annotation type not applicable to this kind of declaration". It was on a line like the following...
@RolesAllowed({"admin", "entryclerk"})
Obviously this is normal to use on a method. Unfortunately, I had it defined on not just any method, but the constructor method of my Java class. It took me awhile to figure out why it was happening, so I thought would spare others a bit of grief.
Safe Shrinking of ext3 LVM volumes
When shrinking your LVM volumes, it is important to do it safely. I will show you how I like to do that here.
