### Question:
ClusterState extends AbstractPersistable implements Solution<Score> { public int countNonIdleHosts() { return hosts.size() - getIdleHosts().size(); } ClusterState(); boolean hostIsIdle(Host host); int countIdleHosts(); int countNonIdleHosts(); List<String> getIdsOfAppsDeployedInHost(Host host); List<Vm> getVmsDeployedInHost(Host host); double avgCpusAssignedPerHost(); int cpusAssignedInHost(Host host); int calculateCumulativeUnusedCpuPerc(); double calculateStdDevCpuPercUsedPerHost(); int countOffHosts(); int countVmMigrationsNeeded(ClusterState destinyClusterState); Vm getVmById(long id); @PlanningEntityCollectionProperty List<Vm> getVms(); void setVms(List<Vm> vms); @ValueRangeProvider(id = "hostRange") List<Host> getHosts(); void setHosts(List<Host> hosts); @Override Score getScore(); @Override void setScore(Score score); @Override Collection<?> getProblemFacts(); @Override String toString();  }### Answer:
@Test public void countNonIdleHosts() { assertEquals(1, clusterState.countNonIdleHosts()); }