* by concurrently running mojo executions. To prevent race conditions, an aggregating execution will block
     * all other executions until finished.
     * We also lock on a given project to forbid a forked lifecycle to be executed concurrently with the project.
     * TODO: ideally, the builder should take care of the ordering in a smarter way

    public void execute(MavenSession session) {
        lifecycleStarter.execute(session);
    }

    // These methods deal with construction intact Plugin object that look like they come from a standard
    // <plugin/> block in a Maven POM. We have to do some wiggling to pull the sources of information
    // together and this really shows the problem of constructing a sensible default configuration but

            this.modelCache = DefaultModelCache.newInstance(session, true);
        }

        ExecutorService createExecutor(int parallelism) {
            //
            // We need an executor that will not block.
            // We can't use work stealing, as we are building a graph
            // and this could lead to cycles where a thread waits for
            // a task to finish, then execute another one which waits

        if (metadataFile.length() == 0) {
            if (!metadataFile.delete()) {
                // sleep for 10ms just in case this is windows holding a file lock
                try {
                    Thread.sleep(10);
                } catch (InterruptedException e) {
                    // ignore
                }

                mojo.execute();
                mojoExecutionListener.afterMojoExecutionSuccess(mojoExecutionEvent);
            } catch (ClassCastException e) {
                // to be processed in the outer catch block
                throw e;
            } catch (RuntimeException e) {
                throw new PluginExecutionException(mojoExecution, project, e);
            }
        } catch (PluginContainerException e) {

        values.add(0, new ScopeState());
    }

    protected ScopeState getScopeState() {
        if (values.isEmpty()) {
            throw new OutOfScopeException("Cannot access session scope outside of a scoping block");
        }
        return values.get(0);
    }

    public void exit() {
        if (values.isEmpty()) {
            throw new IllegalStateException();
        }
        values.remove(0);
    }

                        if (file.exists()) {
                            if (!file.delete()) {
                                // sleep for 10ms just in case this is windows holding a file lock
                                try {
                                    Thread.sleep(10);
                                } catch (InterruptedException ie) {
                                    // ignore