+ " <plugin-group-id>:<plugin-artifact-id>[:<plugin-version>]:<goal>."
                        + " Available lifecycle phases are: " + defaultLifeCycles.getLifecyclePhaseList() + ".");
            }

            int degreeOfConcurrency = session.getRequest().getDegreeOfConcurrency();
            if (degreeOfConcurrency > 1) {

These particular phases in a plugin’s lifecycle can probably be generalized to all plugins so could be something implemented in all plugins. Here we could have the descriptor either point to methods for each of these phases to execute or we could create a lifecycle in Plexus for these phases.

For a particular application plugin there will be a declarative descriptor for that plugin type.

                        + " <plugin-group-id>:<plugin-artifact-id>[:<plugin-version>]:<goal>."
                        + " Available lifecycle phases are: " + defaultLifeCycles.getLifecyclePhaseList() + ".");
            }

            if (logger.isDebugEnabled()) {
                lifecycleDebugLogger.debugReactorPlan(projectBuilds);
            }

          <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>

     1. plugin goal execution in a child is usually simply appended (at end): you can't try to insert in the middle of pre-existing inherited executions,

     2. append happens at plugin level first, then goal level, independently from phases.
        This means for example that adding pluginA:goal2 to pre-existing (pluginA:goal1, pluginB:goal) will lead to (pluginA:goal1, pluginA:goal2, pluginB:goal)

            associated with a Maven project can lack a file. As such, this annotation is meant for Mojos that only
            want to analyze the set of transitive dependencies, in particular during early lifecycle phases where
            full dependency resolution might fail due to projects which haven't been built yet.
          </description>
        </field>
        <field>
          <name>dependencyCollection</name>

      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.
   */

            /*
             * MNG-2277, the check below compensates for our bad plugin support where we ended up with aggregator
             * plugins that require dependency resolution, although they usually run in phases of the build where project
             * artifacts haven't been assembled yet. The prime example of this is "mvn release:prepare".
             */

 ({{{./apidocs/org/apache/maven/model/building/DefaultModelBuilder.html}javadoc}},
 {{{./xref/org/apache/maven/model/building/DefaultModelBuilder.html}source}})
 that manages the steps sequence.

 The sequence is divided into 2 phases:

 * phase 1

   ** profile activation: see {{{./apidocs/org/apache/maven/model/profile/activation/package-summary.html}available activators}}.

    }

    // -----------------------------------------------------------------------------------------------
    // Tests which exercise the lifecycle executor when it is dealing with default lifecycle phases.
    // -----------------------------------------------------------------------------------------------

    @Test
    void testCalculationOfBuildPlanWithIndividualTaskWherePluginIsSpecifiedInThePom() throws Exception {