### Question:
GcpAttachedDiskResourceBuilder extends AbstractGcpComputeBuilder { @Override public List<CloudResource> build(GcpContext context, long privateId, AuthenticatedContext auth, Group group, List<CloudResource> resources, CloudStack cloudStack) throws Exception { InstanceTemplate template = group.getReferenceInstanceTemplate(); List<String> operations = new ArrayList<>(); List<String> syncedOperations = Collections.synchronizedList(operations); String projectId = context.getProjectId(); Compute compute = context.getCompute(); Collection<Future<Void>> futures = new ArrayList<>(); List<CloudResource> buildableResource = resources.stream() .filter(cloudResource -> CommonStatus.REQUESTED.equals(cloudResource.getStatus())) .collect(Collectors.toList()); List<CloudResource> result = new ArrayList<>(); for (CloudResource volumeSetResource : buildableResource) { VolumeSetAttributes volumeSetAttributes = volumeSetResource.getParameter(CloudResource.ATTRIBUTES, VolumeSetAttributes.class); for (VolumeSetAttributes.Volume volume : volumeSetAttributes.getVolumes()) { Disk disk = createDisk(projectId, volume, cloudStack.getTags(), volumeSetAttributes); gcpDiskEncryptionService.addEncryptionKeyToDisk(template, disk); Future<Void> submit = intermediateBuilderExecutor.submit(() -> { Insert insDisk = compute.disks().insert(projectId, volumeSetAttributes.getAvailabilityZone(), disk); try { Operation operation = insDisk.execute(); syncedOperations.add(operation.getName()); if (operation.getHttpErrorStatusCode() != null) { throw new GcpResourceException(operation.getHttpErrorMessage(), resourceType(), disk.getName()); } } catch (GoogleJsonResponseException e) { throw new GcpResourceException(checkException(e), resourceType(), disk.getName()); } return null; }); futures.add(submit); } volumeSetResource.putParameter(OPERATION_ID, operations); result.add(new Builder().cloudResource(volumeSetResource) .status(CommonStatus.CREATED) .params(volumeSetResource.getParameters()) .build()); } for (Future<Void> future : futures) { future.get(); } result.addAll(resources.stream().filter(cloudResource -> CommonStatus.CREATED.equals(cloudResource.getStatus())).collect(Collectors.toList())); return result; }  @Override List<CloudResource> create(GcpContext context, long privateId, AuthenticatedContext auth, Group group, Image image); @Override List<CloudResource> build(GcpContext context, long privateId, AuthenticatedContext auth, Group group,
            List<CloudResource> resources, CloudStack cloudStack); @Override CloudResource delete(GcpContext context, AuthenticatedContext auth, CloudResource resource); @Override ResourceType resourceType(); @Override int order(); @Override List<CloudResourceStatus> checkResources(GcpContext context, AuthenticatedContext auth, List<CloudResource> resources);  }### Answer:
@Test void testBuildWithDiskEncryption() throws Exception { CustomerEncryptionKey encryptionKey = new CustomerEncryptionKey(); encryptionKey.setRawKey("rawKey=="); ArgumentCaptor<Disk> diskCaptor = ArgumentCaptor.forClass(Disk.class); doAnswer(invocation -> { Disk disk = invocation.getArgument(1); disk.setDiskEncryptionKey(encryptionKey); return invocation; }).when(gcpDiskEncryptionService).addEncryptionKeyToDisk(any(InstanceTemplate.class), diskCaptor.capture()); List<CloudResource> build = underTest.build(context, privateId, auth, group, buildableResource, cloudStack); assertNotNull(build); assertEquals(1, build.size()); CloudResource resource = build.iterator().next(); assertEquals(ResourceType.GCP_DISK, resource.getType()); assertEquals(CommonStatus.CREATED, resource.getStatus()); assertEquals("disk", resource.getName()); assertNotNull(diskCaptor.getValue()); assertEquals(encryptionKey, diskCaptor.getValue().getDiskEncryptionKey()); }