Interestingly, though, if you like using typographically correct characters like the ellipsis or quotation marks, you would run into the same issue. For that reason alone I think everything (Your JSP files, server, database, source code etc. should all be able to handle UTF-8)
Nevertheless, the limitation that properties files by default are not cannot be in UTF-8 is quite annoying, as it would require you to escape special non-ISO-8859-1 characters or use a conversion tools such as native2ascii. This blog post summarizes the general issue nicely.
For my project I am using Struts 2.1. By default it does not allow for UTF-8 based message resources. Since Java 6 introduced support for creating a custom loader when accessing resource bundles, I was looking into ways of maybe extending Struts 2. Well, it looks like Struts 2 does neither allow a custom ResourceBundle Control nor for easy patching of Struts itself. See also: https://issues.apache.org/struts/browse/WW-2774
Nevertheless, even though Struts 2.1 improved substantially compared to Struts 2.0.x, I am still debating whether long-term Spring MVC (Especially Spring MVC 3.0) might represent a better choice—With Spring 2.5+ both web frameworks are certainly getting very similar. The nice thing about Spring (Core) is, that it provides the ReloadableResourceBundleMessageSource which provides exactly what was looking for:
Unfortunately, as mentioned above, it looks like there is not an easy pluggable way of convincing Struts 2's textprovider to use Spring's messageSource implementation. As I am already using Spring MVC for some of my actions, I decided to use Spring's message tag
<property name="basename" value="classpath:messages"/>
<property name="defaultEncoding" value="utf-8"/>
Two last questions to answer are:
What is the best way to edit resource bundles using eclipse?
How do ou structure your resource bundles without loosing track of things?
After searching the web for a while, I finally settled for Eclipse Resource Bundle Editor. It works quite nicely, I just wish something useful like this would be built into Eclipse by default.
As for structuring the property files, I settled pretty much on a jsp-by-jsp structure. E.g. if I have a file edit-settings.jsp and I want to customize the page title, then I create a resource bundle entry jsp.edit-settings.title=My settings
Similarily I deal with class files:
class.AddUserAcion.success = The user has been successfully registered.
Just as additional information: I wonder, whether it might be a cool thing, to be able to structure properties files similar to Rails 2.2+. There is an interesting RailsCast available about how to do I18N in Ruby On Rails.