How do you force a maven MOJO to be executed only once at the end of a build?

Question

I have a MOJO I would like executed once, and once only after the test phase of the last project in the reactor to run.

Using:

if (!getProject().isExecut         


        

Answer 1

Check out maven-monitor API

You can add an EventMonitor to the dispatcher, and then trap the END of the 'reactor-execute' event: this is dispatched after everything is completed, i.e. even after you see the BUILD SUCCESSFUL/FAILED output.

Here's how I used it recently to print a summary right at the end:

/**
 * The Maven Project Object
 *
 * @parameter expression="${project}"
 * @required
 * @readonly
 */
protected MavenProject project;


/**
 * The Maven Session.
 *
 * @parameter expression="${session}"
 * @required
 * @readonly
 */
protected MavenSession session;

...


@Override
public void execute() throws MojoExecutionException, MojoFailureException
{
    //Register the event handler right at the start only
    if (project.isExecutionRoot())
        registerEventMonitor();
    ...
}


/**
 * Register an {@link EventMonitor} with Maven so that we can respond to certain lifecycle events
 */
protected void registerEventMonitor()
{
    session.getEventDispatcher().addEventMonitor(
            new EventMonitor() {

                @Override
                public void endEvent(String eventName, String target, long arg2) {
                    if (eventName.equals("reactor-execute"))
                        printSummary();
                }

                @Override
                public void startEvent(String eventName, String target, long arg2) {}

                @Override
                public void errorEvent(String eventName, String target, long arg2, Throwable arg3) {}


            }
    );
}


/**
 * Print summary at end
 */
protected void printSummary()
{
    ...
}