code: protected DependencyNode getRootNodeDependecyTree() throws MojoExecutionException{
      try {
        ArtifactFilter artifactFilter = null;
  
        // works for only maven 3. Use of dependency graph component not handled for maven 2
        // as current version of NAR already requires Maven 3.x
        rootNode = dependencyGraphBuilder.buildDependencyGraph(getMavenProject(), artifactFilter);
  
      } catch (DependencyGraphBuilderException exception) {
        throw new MojoExecutionException("Cannot build project dependency graph", exception);
      }
  
      return rootNode;
    }
docs: Get root node of the current Maven project Dependency tree generated by
  maven.shared dependency graph builder.
  
  @return root node of the project Dependency tree
  @throws MojoExecutionException