code: @BetaApi
    public final AggregatedListTargetInstancesPagedResponse aggregatedListTargetInstances(
        String project) {
      AggregatedListTargetInstancesHttpRequest request =
          AggregatedListTargetInstancesHttpRequest.newBuilder().setProject(project).build();
      return aggregatedListTargetInstances(request);
    }
docs: Retrieves an aggregated list of target instances.
  
  <p>Sample code:
  
  <pre><code>
  try (TargetInstanceClient targetInstanceClient = TargetInstanceClient.create()) {
  ProjectName project = ProjectName.of("[PROJECT]");
  for (TargetInstancesScopedList element : targetInstanceClient.aggregatedListTargetInstances(project.toString()).iterateAll()) {
  // doThingsWith(element);
  }
  }
  </code></pre>
  
  @param project Project ID for this request.
  @throws com.google.api.gax.rpc.ApiException if the remote call fails