Apache Maven 2: Effective Implementation Sample Chapter

When I announced the release of the book last week, I neglected to mention that there is a sample chapter online. It is available from the book’s site, but can be directly downloaded as a PDF:

• Chapter 6 – Useful Maven Plugins

There is also an excerpt online if you don’t like PDF.

While it does stand alone, the examples are also worked in to the context of the sample project used throughout the book where appropriate.

This chapter was a late inclusion, but turned out to be one of my favourites. While it doesn’t cover all the useful Maven plugins (many such as the Enforcer and Assembly plugins are picked up elsewhere in the book), it highlights some that aren’t always well known or used:

• The Remote Resources plugin – and particularly the right pattern for including a package of reusable resources
• The Build Number plugin
• The Shade plugin – a very useful way to handle redistributing JARs and “uberJARs” and reducing dependency and classloading issues
• The Build Helper plugin – useful bits and pieces like additional artifacts to deploy and reserved network ports for tests
• The AntRun plugin (and other scripting languages) – how to still use Ant without the guilt of violating The Maven Way!
• The Exec plugin – fork an external process in your build, or configure it for running your standalone application easily from the POM

I do think if there was one plugin I would have liked to cover more in this centralised location it would have been the Enforcer – perhaps pulling some entries together would make a good blog topic in the future though.

I hope you enjoy the sample chapter and consider buying the book!

Selenium Maven Plugin 1.0 Released

The Selenium Maven plugin 1.0 has now been released, taking advantage of the recent Selenium 1.0.1 release. This will be useful to those using Firefox 3 for example which required a workaround in the previous version.

This is the first stable release version of the plugin. Full credit goes to Jason Dillon for his work on the plugin to get it to this point!

I will be following up with some posts on some tips for its use in the coming days.

In the mean time, here are the release notes since 1.0-rc-1:

Bug

• [MSELENIUM-20] – Starting the selenese goal using selenium-maven-plugin
• [MSELENIUM-39] – firefoxProfileTemplate parameter does not work
• [MSELENIUM-43] – Invalid constructor used by selenese goal to construct SeleniumServer
• [MSELENIUM-49] – Invalid dependency version for ‘org.openqa.selenium.client-drivers’ in site example

Improvement

• [MSELENIUM-30] – Add displayPropertiesFile support for selenium:selenese goal
• [MSELENIUM-40] – Using a remote selenium server with Selenese.
• [MSELENIUM-50] – Upgrade to Selenium 1.0

New Feature

• [MSELENIUM-38] – Start Selenium Server with a Proxy via System Properties

Reactor: My New Favourite Maven Plugin

Dan recently put together a great new plugin to manipulate the Maven reactor, currently being voted on for release.

It has a few goals:

• reactor:resume – pick up where a previous build left off
• reactor:make / make-dependents – make a project and its dependencies or those that depend on it
• reactor:make-scm-changes – make any projects that have uncommitted changes and their dependencies

This is particularly useful for building a subset of modules during development to reduce the time of a build. While it is a good practice to break down your build into a structure that might reflect common build scenarios, this will be useful in plenty of circumstances.

Think about the 10 minute build that fails with a missing dependency about 9 minutes in, but still with 5 modules to build. You don’t want to build it all again, and you don’t want to build 5 modules manually. Now, you just fix the dependency problem (say, by adding a new proxy/artifact to your locked down repository manager), then run mvn reactor:resume -Dfrom=module-that-failed. Simple!

As I mentioned in an earlier post, this same functionality is intended to be built natively into the final Maven 2.1.0 release (with some exceptions) – keep an eye out for it!