Not that long ago I gave a ThoughtWorks geek night presentation on Post-Redirect-Get and how to mess with the Spring Framework to make it happen. I've put up the presentation and the code that I used for it on GitHub. Feedback is always welcome....
Here is how I set up the Apache Ivy dependency manager so that it can fetch springframework JARs from the SpringSource Enterprise Bundle Repository. Listing: ivysettings-custom.xml <ivysettings> <resolvers> <url name="com.springsource.repository.bundles.release"> <ivy pattern="http://repository.springsource.com/ivy/bundles/release/[organisation]/[module]/[revision]/[artifact]-[revision].[ext]" /> <artifact pattern="http://repository.springsource.com/ivy/bundles/release/[organisation]/[module]/[revision]/[artifact]-[revision].[ext]" /> </url> <url name="com.springsource.repository.bundles.external"> <ivy pattern="http://repository.springsource.com/ivy/bundles/external/[organisation]/[module]/[revision]/[artifact]-[revision].[ext]" /> <artifact pattern="http://repository.springsource.com/ivy/bundles/external/[organisation]/[module]/[revision]/[artifact]-[revision].[ext]" /> </url> <chain name="spring"> <resolver ref="com.springsource.repository.bundles.release"/> <resolver ref="com.springsource.repository.bundles.external"/> </chain> <ibiblio name="jboss" root="http://repository.jboss.org/maven2/" m2compatible="true"/> <chain name="main" dual="true"> <resolver ref="shared" /> <resolver ref="public" /> <resolver ref="spring" /> <resolver ref="jboss" /> </chain> <chain name="default" returnFirst="true"> <resolver ref="local" /> <resolver ref="main" /> </chain> </resolvers> </ivysettings> Listing: ivysettings....
HTML is notoriously difficult to parse and it has usually been a pain to do this in Java. Yes I know that there are parsers (like jtidy and nekohtml) that try to create a proper DOM but I’ve been waiting for something more lightweight. Enter Jsoup. It feels like a mix of JQuery and Beautiful Soup (for Python). String html = response.getContentAsString(); Document document = Jsoup.parse(html); Elements elements = document.select("#errorRef"); assertThat(elements....
StringTemplate is a great templating engine. It's powerful, simple and quite opinionated. I've come really appreciate its simple purpose: render data. No assignment, no arbitrary method invocation. It is not Turing-complete and it would make a lousy rules engine. SiteMesh is a web-page layout and decoration framework that is my current "golden hammer" when I need to provide a consistent layout across a java web-application. It seems to fit with the way that I think about web pages a whole lot more than something like Tiles - I really prefer decoration over composition as a means of layout control....
My day-to-day work often consists of writing web applications that aggregate data from a number of sources. Corporate constraints frequently dictate that I cannot use languages that make crunching of collections easier so I am forced into an old-fashioned for-loop frenzy. Ugh. On a recent java project my pairing buddy (Jules - thank you) suggested that we look at lambdaj. From the lamdbaj site: “lambdaj is a library that makes easier to address this issue by allowing to manipulate collections in a pseudo-functional and statically typed way”....
One of the best descriptions of the hierarchy of tests that I have seen comes from "Growing Object-Oriented Software, Guided by Tests" by Steve Freeman and Nat Price. 1. Acceptance Tests: Does the whole system work? 2. Integration Tests: Does our code work against code we can't change? 3. Unit Tests: Do our objects do the right thing, are they convenient to work with? Can we now get on with some work, rather than discussing definitions ad nauseam?...
For a while now I've been flying the flag for using a post-redirect-get design pattern when writing web applications. In my opinion the current crop of web frameworks still make it very easy to do the "bad" thing since to do PRG properly you need to think what kind of an interaction you want with users and not cop out saying its technically very difficult in . If you resort to ActiveX controls, popups without navigation bars and/or weird javascript hacks to stop users from clicking refresh or back buttons then perhaps you should have written a better web application....
I've been saving this rant for a while now: 1. Test everything at the front-end, in exquisite detail - every project sponsor understands what tooltip 0 really means. Also a great idea if you like long-running and fragile tests that require deployments, browsers, testing frameworks and the kitchen sink. Testing at different layers, and perhaps even without a browser or (in java) a servlet container is for the weak. 2. Perform a database cleanup before and after every test, whether it needs to be done or not....
I like non-sequential identifiers for resources. Easy to do in Java (with java.util.UUID) and in Python (using the uuid module). This has been a bit of a pain in Rails, until now - check out Ariejan de Vroom's post. I especially like his solution as it plays well with RSpec, although to be picky I would have chosen UUID.random_create rather than UUID.timestamp_create....
The Jersey JAX-RS project provides bindings for springframework and google-guice. However I wanted to see what it would take to use PicoContainer as an IoC container within Jersey. Verdict: not much at all. Nicely extensible. To see what I mean please take a look at my jersey-pico project on GitHub. I can now create JAX-RS services in Java or Groovy with a very simple IoC container....