code: @BetaApi
    public final Operation enableXpnResourceProject(
        ProjectName project,
        ProjectsEnableXpnResourceRequest projectsEnableXpnResourceRequestResource) {
  
      EnableXpnResourceProjectHttpRequest request =
          EnableXpnResourceProjectHttpRequest.newBuilder()
              .setProject(project == null ? null : project.toString())
              .setProjectsEnableXpnResourceRequestResource(projectsEnableXpnResourceRequestResource)
              .build();
      return enableXpnResourceProject(request);
    }
docs: Enable service resource (a.k.a service project) for a host project, so that subnets in the host
  project can be used by instances in the service project.
  
  <p>Sample code:
  
  <pre><code>
  try (ProjectClient projectClient = ProjectClient.create()) {
  ProjectName project = ProjectName.of("[PROJECT]");
  ProjectsEnableXpnResourceRequest projectsEnableXpnResourceRequestResource = ProjectsEnableXpnResourceRequest.newBuilder().build();
  Operation response = projectClient.enableXpnResourceProject(project, projectsEnableXpnResourceRequestResource);
  }
  </code></pre>
  
  @param project Project ID for this request.
  @param projectsEnableXpnResourceRequestResource
  @throws com.google.api.gax.rpc.ApiException if the remote call fails