### Question:
BigtableClusterName { public String getClusterId() { return clusterId; } @InternalApi("For internal usage only")  BigtableClusterName(String clusterName); @Override String toString(); String getInstanceId(); String getClusterName(); String getClusterId(); String toSnapshotName(String snapshotId);  }### Answer:
@Test public void getClusterId() { String clusterName = "projects/proj/instances/inst/clusters/cluster1"; Assert.assertEquals("cluster1", new BigtableClusterName(clusterName).getClusterId()); }