Using Maven Archetypes

The quickstart archetype is a simple project with JAR packaging and a single dependency on JUnit. After generating a project with the quickstart archetype, you will have a single class named App in the default package with a main() method that prints "Hello World!" to standard output. You will also have a single JUnit test class named AppTest with a testApp() method with a trivial unit test.

This archetype creates a simple project with WAR packaging and a single dependency on JUnit. ${basedir}/src/main/webapp contains a simple shell of a web application: an index.jsp page and the simplest possible web.xml file. Even though the archetype includes a dependency on JUnit, this archetype does not create any unit tests. If you were looking for a functional web application, this archetype is going to disappoint you. For more relevant web archetypes, see Section 12.3.2, “Notable Third-Party Archetypes”.

This archetype creates a simple project with maven-plugin packaging and a single mojo class named MyMojo in the project’s default package. The MyMojo class contains a touch goal which is bound to the process-resources phase, it creates a file named touch.txt in the target/ directory of the new project when it is executed. The new project will have a dependency on maven-plugin-api and JUnit.

AppFuse is an application framework developed by Matt Raible. You can think of AppFuse as something of a Rosetta Stone for a few very popular Java technologies like the Spring Framework, Hibernate, and iBatis. Using AppFuse you can very quickly create an end-to-end multi-tiered application that can plugin into several front-end web frameworks like Java Server Faces, Struts, and Tapestry. Starting with AppFuse 2.0, Matt Raible has been transitioning the framework to Maven 2 to take advantage of the dependency management and archetype capabilities. AppFuse 2 provides the following archetypes all in the groupId org.appfuse.archetypes:

appfuse-basic-jsf and appfuse-modular-jsf

End-to-end application using Java Server Faces in the presentation layer

appfuse-basic-spring and appfuse-modular-spring

End-to-end application using Spring MVC in the presentation layer

appfuse-basic-struts and appfuse-modular-struts

End-to-end application using Struts 2 in the presentation layer

appfuse-basic-tapestry and appfuse-modular-tapestry

End-to-end application using Tapestry in the presentation layer

appfuse-core

Persistence and object model without the presentation layer

Archetypes following the appfuse-basic-* pattern are entire end-to-end applications in a single Maven project, and archetypes following the appfuse-modular-* pattern are end-to-end applications in a multimodule Maven project which separates the core model objects and persistence logic from the web front-end. Here’s an example from generating a project to running a web application for the modular Spring MVC application:

$ mvn archetype:generate \
-DarchetypeArtifactId=appfuse-modular-spring \
-DarchetypeGroupId=org.appfuse.archetypes \
-DgroupId=org.sonatype.mavenbook \
-DartifactId=mod-spring \
-Dversion=1.0-SNAPSHOT \
-DinteractiveMode=false[INFO] Scanning for projects...
...
[INFO] [archetype:generate]
[INFO] Generating project in Batch mode
[INFO] Archetype [org.appfuse.archetypes:appfuse-modular-spring:RELEASE]
found in catalog
[INFO] Parameter: groupId, Value: org.sonatype.mavenbook
[INFO] Parameter: packageName, Value: org.sonatype.mavenbook
[INFO] Parameter: basedir, Value: /Users/tobrien/tmp
[INFO] Parameter: package, Value: org.sonatype.mavenbook
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: artifactId, Value: mod-spring
...
[INFO] OldArchetype created in dir: /Users/tobrien/tmp/mod-spring
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESSFUL
$ cd mod-spring
$ mvn
... (an overwhelming amount of activity ~5 minutes)
$ cd web
$ mvn jetty:run-war
... (Maven Jetty plugin starts a Servlet Container on port 8080)

From generating a project with the AppFuse archetype to running a web application with a authentication and user-management system takes all of 5 minutes. This is the real power of using a Maven Archetype as a foundation for a new application. We oversimplified the AppFuse installation process a bit and left out the important part where you download and install a MySQL database, but that’s easy enough to figure out by reading the AppFuse Quickstart Documentation.

Atlassian has created some archetypes for people interested in developing plugins for both Confluence and JIRA. Confluence and JIRA are, respectively, a Wiki and an issue tracker both of which have gained a large open source user base through granting free licenses for open source projects. Both the jira-plugin-archetype and the confluence-maven-archetype artifacts are under the com.atlassian.maven.archetypes groupId. When you generate a Confluence plugin, the archetype will generate a pom.xml which contains the necessary references to the Atlassian repositories and a dependency on the confluence artifact. The resulting Confluence plugin project will have a single example macro class and an atlassian-plugin.xml descriptor. Generating a project from the Jira archetype creates a project with a single, blank MyPlugin class and an atlassian-plugin.xml descriptor in ${basedir}/src/main/resources.

For more information about developing Confluence plugins with Maven 2, see Developing Confluence Plugins with Maven 2 on the Confluence project’s Wiki. For more information about developing Jira plugins with Maven 2, see How to Build and Atlassian Plugin on the Atlassian Developer Network.

Apache Wicket is a component-oriented web framework which focused on managing the server-side state of a number of components written in Java and simple HTML. Where a framework like Spring MVC or Ruby on Rails focuses on merging objects within a request with a series of page templates, Wicket is very strongly focused on capturing interactions and page structure in a series of POJO Java classes. In an age where hype-driven tech media outlets are proclaiming the "Death of Java", Wicket is a contrarian approach to the design and assembly of web applications. To generate a Wicket project with the Maven Archetype plugin:

$ mvn archetype:generate
... (select the "wicket-archetype-quickstart" artifact from the interactive \
menu) ...
... (supply a groupId, artifactId, version, package) ...
... (assuming the artifactId is "ex-wicket") ...
$ cd ex-wicket
$ mvn install
... (a lot of Maven activity) ...
$ mvn jetty:run
... (Jetty will start listening on port 8080) ...

Just like the AppFuse archetype, this archetype creates a shell web application which can be immediately executed with the Maven Jetty plugin. If you hit http://localhost:8080/ex-wicket, you be able to see the newly created web application in a servlet container.