Open Source projects are known for dodgy websites, and rubbish documentation. I was overjoyed to see a project that got it right (URL Rewrite Filter). There are a number of things that I really appreciated with this site, and in the hope that people might take notice, I’m going to list the good bits here.

The landing home page has a nice concise description of what the project is all about. When I get to the front page, I can read the overview of the project, and get an understanding of what problems it was created for, and the goals of it. The front page told me enough to want to see more, but didn’t overwhelm me. I got a good feeling from the front page.

The other nice thing about the front page is the navigation structure. The side navigation bar provides the links which I am most interested in. One click to get to a download link (which has a direct link to the files). One click to the source code page (with instructions on svn access via http and the commandline). One click to the documentation. One click to get to the community support.

The documentation is excellent, and provides a good baseline for what documentation of a project this size should look like.

There are good examples of what the configuration file looks like, annotated in a way that makes it easy to understand what the code is there for.

The documentation provides a good reference for how to do the configuration.

It is a great site and provides a good example of what most open source project websites should look like.

Making the browser location work like a command prompt is a good goal for any web application, and is possible for any J2EE web framework, even Struts 1.

To do this, having Rails style friendly urls is required. Traditionally J2EE frameworks and applications have not done a good job of providing friendly urls. It is easy to wander around the net and guess at what framework people used by the urls (e.g. anything .do is probably struts, .action’s are probably webwork etc.)

Of course one doesn’t have to be tied to this world. Pretty much anything is possible with Apache and mod-rewrite. This is handy when you are behind Apache, but that isn’t always the case. From time-to-time you may want to dot his completely within your J2EE application, making it independant of where you are running. The Servlet spec is powerful enough to make this possible, but for the lazy (like me) it is nice to know that someone has already done the hard work. The URL Rewrite library provides a filter which does the heavy lifting for you. There is a simple XML configuration file, which provides a rich language for customising your redirects using the Java Regex library, or a familiar directory traversal wildcard style syntax.

The library makes it possible to easily map urls like: products/1 to products.do?productId=1 or from: /australia/queensland/brisbane to: worldMap.jspa?country=australia&state=queensland&city=brisbane. There is a rich syntax for specifying the url rewrite conditions, as described in the comprehensive manual, and shown in the samples.

This post is the first in a series of efforts to clean up my list of drafts.  This particular post is probably about a year old.  It is somewhat fitting that it is the first in my effort to clean out my drafts .  Before making each post in this series I'll edit the post to clean it up, and add new comments in italics, or footnotes).

I often spend time talking about different things with my wife, Suzanne. We both like learning, and sharing from our different experiences (in fact I'd almost call Suzanne a compulsive learner). 

I was recently struggling with an application with memory leaks1. When explaining this to Suzanne (who is currently working in a hospital setting treating a lot of kids with enuresis and encopresis)2, she pointed out that it is probably more of a case of memory constipation.

Especially in an environment with Garbage collection. The issue is that the rubbish ain’t getting out of the system.

1 - That was two years ago, in a Swing fat client.  Two years later at Ephox we getting OutOfMemoryExceptions in Java Applets↩

2 - actually now she is a full time Mum, and doing some Enjo demos on the side.↩

Join me on a journey through using ruby to generate java, learning how to use the built in ruby templating tool erb, and some of the rubyish techniques that erb leverages.

 Our adventure starts with a need to generate a large number of very simple java classes in order to have a nice simple test case for the boys at sun.  The requirements for the classes are:

1. they are some how different
2. it is easy to tell when each class is loaded by the class loader
3. it is easy to tell when each class is instantiated

These requirements would be painful to meet (when creating 1000+ classes) even in the most powerful java IDE.  An automated technique for generating code.  In steps Ruby and erb.

A basic ruby script which has a simple template to base the files on, and creates the java classes.

#

                   #merge the template into the file, passing in the current binding.

In looking back over the example, you can see some interesting rubyisms.  These are some of the spots where ruby is revealed. Note the following:

• the use of closures (File.open, and 5.times),
• everything really is an object (the method times being called on the object literal 5),
• heredoc notation (<<EOF )
• the ease of templating with erb (which keeps normal ruby syntax in the template),

The statement I made above about everything being an object is pushed to its limits when looking at the method call:

.  The binding method is available as a part of the Kernel, a mixin(providing methods for use) that is a part of Object, the mighty superclass of everything in Ruby.  This method will return a Binding object, which erb uses to get data to merge into the template.

The File.open line opens a file in write mode, overriding the contents of the file.  For more examples of how to do this, look at the PLEAC site, which has a good set of ruby file examples, and quite a complete set of ruby examples.  This is an excellent resource for learning a language.

In all, Ruby does a good job of working with files, and templating.  Erb is a great tool for templating, and forms the backbone of many well known ruby programs.

I was pleasantly surprised to see a blog entry pop up in my feed reader mentioning subscription accounts for InvoicePlace. As I was one of the guys who helped write the code that is behind InvoicePlace (using a Java Web stack), I take pride in seeing it move closer to being a great success. InvoicePlace provides a great, simple, easy to use tool to help enter and keep track of invoices. It works really well for people and businesses send invoices, and want to be able to manage these electronically.

I've been sipping the InvoicePlace Champagne for quite a while now (it tastes much better than dog food), starting to use InvoicePlace to bill Growthbase before the name InvoicePlace had formed more than a glimmer in Scott's eye. I found InvoicePlace really useful, and expect that it will continue to grow and evolve in positive ways. Some of the features that I was able to exploit to help manage my invoicing needs in my development version were nice, and I expect that in due time they will be released and made available to the public.

I definitely have fond memories of my time working on the project, and the late nights spent adding functionality, and working hard at trying to push the test coverage and quality up. I look forward to following the continuing progress of InvoicePlace, and will use this site whenever I need to issue invoices.

As the title implies, this utility updates a file (files) and sets the last modified date:

It’s free, and (being Java) it’s cross platform……

ok so there aren’t really many platforms apart from Windows that don’t have “touch” built in, but it is still kinda cool .