*
     * @return the collection of phases in Maven 3 compatible ordering
     */
    default Collection<Phase> v3phases() {
        return phases();
    }

    /**
     * Stream of phases containing all child phases recursively.
     *
     * @return a stream of all phases in this lifecycle, including nested phases
     */
    default Stream<Phase> allPhases() {
        return phases().stream().flatMap(Phase::allPhases);
    }

 * <p>
 * This interface allows plugins and extensions to define and register additional build lifecycles
 * beyond the standard ones provided by Maven (like clean, default, site). Lifecycles define a sequence
 * of phases that can be executed during a build.
 * <p>
 * Implementations of this interface will be discovered through the Java ServiceLoader mechanism
 * and their provided lifecycles will be available throughout the Maven build process.

 */
package org.apache.maven.api;

import java.util.Optional;

import org.apache.maven.api.annotations.Experimental;
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 {

    /**

     * present, are appended, to those specified on CLI input, if any.
     */
    Optional<String> atFile();

    /**
     * Returns the list of goals and phases to execute.
     *
     * @return an {@link Optional} containing the list of goals and phases to execute, or empty if not specified
     */
    @Nonnull
    Optional<List<String>> goals();

          <version>1.0.0+</version>
          <type>String</type>
          <description>The ID of this lifecycle, for identification in the mojo descriptor.</description>
        </field>
        <field>
          <name>phases</name>
          <version>1.0.0+</version>
          <description>The phase mappings for this lifecycle.</description>
          <association>
            <type>Phase</type>
            <multiplicity>*</multiplicity>

      listeners.get(i).dispatch();
    }
  }

  /**
   * A special purpose queue/executor that dispatches listener events serially on a configured
   * executor. Each event can be added and dispatched as separate phases.
   *
   * <p>This class is very similar to {@link SequentialExecutor} with the exception that events can
   * be added without necessarily executing immediately.
   */