### Question:
GcpComputeInstanceContainer extends Container { @Override public boolean isCattle () { return createdBy != null; } private  GcpComputeInstanceContainer(); static GcpComputeInstanceContainerBuilder builder(); String getUniqueIdentifier(); @ChaosExperiment(experimentType = ExperimentType.STATE, experimentScope = ExperimentScope.CATTLE, maximumDurationInSeconds = 600) void recreateInstanceInGroup(Experiment experiment); String getInstanceName(); String getZone(); @Override Platform getPlatform(); @Override String getSimpleName(); @Override String getAggregationIdentifier(); @Override DataDogIdentifier getDataDogIdentifier(); @Override boolean isCattle(); @ChaosExperiment(experimentType = ExperimentType.NETWORK, experimentScope = ExperimentScope.PET) void removeNetworkTags(Experiment experiment); @ChaosExperiment(experimentType = ExperimentType.RESOURCE, maximumDurationInSeconds = 600) void simulateMaintenance(Experiment experiment); @ChaosExperiment(experimentType = ExperimentType.STATE, experimentScope = ExperimentScope.PET) void stopInstance(Experiment experiment); @ChaosExperiment(experimentType = ExperimentType.STATE, experimentScope = ExperimentScope.PET) void resetInstance(Experiment experiment); GcpSSHKeyMetadata getGcpSSHKeyMetadata(); void updateUUID(); SSHCredentials getSSHCredentials(); String getSSHEndpoint(); @Override boolean supportsShellBasedExperiments(); static final String DATADOG_IDENTIFIER_KEY; }### Answer:
@Test public void isCattle () { GcpComputeInstanceContainer otherContainer = GcpComputeInstanceContainer.builder().build(); assertNotNull(container.getAggregationIdentifier()); assertNull(otherContainer.getAggregationIdentifier()); assertTrue(container.isCattle()); assertFalse(otherContainer.isCattle()); }