code: public static List<ResourceRoot> allResourceRoots(DeploymentUnit deploymentUnit) {
          List<ResourceRoot> roots = new ArrayList<ResourceRoot>();
          // not all deployment units have a deployment root
          final ResourceRoot deploymentRoot = deploymentUnit.getAttachment(Attachments.DEPLOYMENT_ROOT);
          if (deploymentRoot != null)
              roots.add(deploymentRoot);
          roots.addAll(deploymentUnit.getAttachmentList(Attachments.RESOURCE_ROOTS));
          return roots;
      }
docs: Get all resource roots for a {@link DeploymentUnit}
  
  @param deploymentUnit The deployment unit
  @return The deployment root and any additional resource roots