import org.apache.maven.api.annotations.Nonnull;

/**
 * Event sent by maven during various phases of the build process.
 * Such events can be listened to using {@link Listener}s objects
 * registered in the {@link Session}.
 *
 * @since 4.0.0
 */
@Experimental
public interface Event {

    /**
     * Gets the type of the event.
     *
     * @return the type of the event, never {@code null}
     */
    @Nonnull

                    listener.sessionEnded(event);
                    break;

                case ProjectSkipped:
                    listener.projectSkipped(event);
                    break;
                case ProjectStarted:
                    listener.projectStarted(event);
                    break;
                case ProjectSucceeded:
                    listener.projectSucceeded(event);
                    break;

        // default does nothing
    }

    public void projectSucceeded(ExecutionEvent event) {
        // default does nothing
    }

    public void projectFailed(ExecutionEvent event) {
        // default does nothing
    }

    public void forkStarted(ExecutionEvent event) {
        // default does nothing
    }

    public void forkSucceeded(ExecutionEvent event) {

    @Override
    public void buildExtensionsAssembled(ModelBuildingEvent event) {
        Model model = new Model(event.model());

        try {
            pluginRepositories = projectBuildingHelper.createArtifactRepositories(
                    model.getPluginRepositories(), pluginRepositories, projectBuildingRequest);
        } catch (Exception e) {
            event.problems()
                    .add(

                assertNotNull(event.getSession());
                assertNotNull(event.getProject());
                assertNotNull(event.getExecution());
                assertNotNull(event.getMojo());
                assertNull(event.getCause());

                log.add("beforeMojoExecution " + event.getProject().getArtifactId() + ":"

     *
     * @param event The details about the event.
     */
    default void buildExtensionsAssembled(ModelBuildingEvent event) {}

        }
    }

    public void afterProjectExecutionSuccess(ProjectExecutionEvent event) throws LifecycleExecutionException {
        for (ProjectExecutionListener listener : listeners) {
            listener.afterProjectExecutionSuccess(event);
        }
    }

    public void afterProjectExecutionFailure(ProjectExecutionEvent event) {

        }
    }

    @Override
    public void afterProjectExecutionSuccess(ProjectExecutionEvent event) throws LifecycleExecutionException {
        for (ProjectExecutionListener listener : listeners) {
            listener.afterProjectExecutionSuccess(event);
        }
    }

    @Override
    public void afterProjectExecutionFailure(ProjectExecutionEvent event) {

        RepositoryEvent.Builder event = new RepositoryEvent.Builder(session, EventType.ARTIFACT_DESCRIPTOR_MISSING);
        event.setTrace(trace);
        event.setArtifact(artifact);
        event.setException(exception);

        repositoryEventDispatcher.dispatch(event.build());
    }

    private void invalidDescriptor(

    void beforeProjectExecution(ProjectExecutionEvent event) throws LifecycleExecutionException;

    void beforeProjectLifecycleExecution(ProjectExecutionEvent event) throws LifecycleExecutionException;

    void afterProjectExecutionSuccess(ProjectExecutionEvent event) throws LifecycleExecutionException;

    void afterProjectExecutionFailure(ProjectExecutionEvent event);