public static void modifyInstanceWithExtendedMemory()

in compute/cloud-client/src/main/java/compute/custommachinetype/UpdateMemory.java [53:125]
51 lines of code
8 McCabe index (conditional complexity)

  public static void modifyInstanceWithExtendedMemory(
      String project, String zone, String instanceName, int newMemory)
      throws IOException, ExecutionException, InterruptedException, TimeoutException {
    // Initialize client that will be used to send requests. This client only needs to be created
    // once, and can be reused for multiple requests. After completing all of your requests, call
    // the `instancesClient.close()` method on the client to safely
    // clean up any remaining background resources.
    try (InstancesClient instancesClient = InstancesClient.create()) {

      // Create the get instance request object.
      GetInstanceRequest getInstanceRequest = GetInstanceRequest.newBuilder()
          .setProject(project)
          .setZone(zone)
          .setInstance(instanceName)
          .build();

      Instance instance = instancesClient.get(getInstanceRequest);

      // Check the machine type.
      if (!(instance.getMachineType().contains("machineTypes/n1-")
          || instance.getMachineType().contains("machineTypes/n2-")
          || instance.getMachineType().contains("machineTypes/n2d-"))) {
        System.out.println("extra memory is available only for N1, N2 and N2D CPUs");
        return;
      }

      // Make sure that the machine is turned off.
      if (!(instance.getStatus().equals(Status.TERMINATED.toString())
          || instance.getStatus().equals(Status.STOPPED.toString()))) {

        StopInstanceRequest stopInstanceRequest = StopInstanceRequest.newBuilder()
            .setProject(project)
            .setZone(zone)
            .setInstance(instanceName)
            .build();

        OperationFuture<Operation, Operation> operation = instancesClient.stopAsync(
            stopInstanceRequest);
        Operation response = operation.get(3, TimeUnit.MINUTES);
        if (response.hasError()) {
          System.out.printf("Unable to stop instance %s", response.getError());
          return;
        }
      }

      // Modify the machine definition. Note that extended memory
      // is available only for N1, N2 and N2D CPUs.
      String machineType = instance.getMachineType();
      String start = machineType.substring(0, machineType.lastIndexOf("-"));

      // Create the machine type instance request object.
      SetMachineTypeInstanceRequest setMachineTypeInstanceRequest =
          SetMachineTypeInstanceRequest.newBuilder()
              .setProject(project)
              .setZone(zone)
              .setInstance(instanceName)
              .setInstancesSetMachineTypeRequestResource(InstancesSetMachineTypeRequest.newBuilder()
                  .setMachineType(String.format("%s-%d-ext", start, newMemory))
                  .build())
              .build();

      // Invoke the API with the request object and wait for the operation to complete.
      Operation response = instancesClient.setMachineTypeAsync(setMachineTypeInstanceRequest)
          .get(3, TimeUnit.MINUTES);

      // Check for errors.
      if (response.hasError()) {
        System.out.printf("Unable to update instance %s", response.getError());
        return;
      }
      System.out.println("Instance updated!");
    }
  }