Section 1.14. Generating an Ant Build File | Maven: A Developers Notebook (Developers Notebooks)

1.14. Generating an Ant Build File

There are times when you will want to build using Apache Ant. Maybe your project is using an automated process which relies on Ant, or maybe you have some team members who are not yet comfortable making the transition to Maven and who wish to continue using Ant. Since many IDEs already support projects with Ant build files, you can use Maven to generate a build.xml file so that your project can be built using Apache Ant.

1.14.1. How do I do that?

Run the Ant plug-in. Running maven ant will create a build.xml file which contains targets to gather dependencies, build, and test your application. Take a look at the output of running the default jar target:

C:\dev\mavenbook\code\genapp\test-application>ant Buildfile: build.xml    init:     [mkdir] Created dir: C:\dev\mavenbook\code\genapp\target\lib    get-deps:       [get] Getting: http://www.ibiblio.org/maven/springframework/jars/spring-core-1.1.4.jar       [get] Getting: http://www.ibiblio.org/maven/springframework/jars/spring-web-1.1.4.jar    compile:      [copy] Copying 1 file to C:\dev\mavenbook\code\genapp\target\classes    junit-present:      [echo]  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  = WARNING =  =  =  = =   =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =      [echo] Junit isn't present in your ${ANT_HOME}/lib directory. Tests not executed.      [echo] =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =   =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =  =      compile-tests:    internal-test:    test:    jar:       [jar] Building jar: C:\dev\mavenbook\code\genapp\test-application\target\ test-application-1.0.jar    BUILD SUCCESSFUL Total time: 2 seconds

You may have noticed that there is a problem, and it is an illustrative problem. Apache Ant does not automatically manage the dependencies for optional Ant tasks. If you want to run the JUnit tests, you will need to copy the junit-3.8.1.jar file from the local Maven repository to ${ANT_HOME}/lib. This build file contains a get-deps target which executes the Ant get task to grab all of the project's dependencies from the remote Maven repository at http://www.ibiblio.org/maven.

1.14.2. What about...

...trying to get away from Ant? Isn't Maven a replacement for Ant?

Yes and no. Ant isn't "bad," and the majority of tools still work with Ant. There is no reason not to provide interoperability with Apache Ant, and once you learn more about Jelly in Section 2.1, you'll see that Ant tasks are used extensively in Maven. Many projects use a continuous integration system which may expect an Ant build file. Running maven ant provides an easy way to continue to support these tools.

Note: Although this is changing rapidly; many tools such as AntHill and Gump are starting to support both Ant and Maven. But, if you are still working with a tool that expects an Ant build file, run maven ant.