code: @Test public void testCreateClusterWithHostMapping() throws AmbariException {
    Set<String> hostNames=new HashSet<String>();
    hostNames.add("h1");
    hostNames.add("h2");
    ClusterRequest r=new ClusterRequest(null,"c1","HDP-0.1",hostNames);
    try {
      controller.createCluster(r);
      fail("Expected create cluster to fail for invalid hosts");
    }
   catch (  Exception e) {
    }
    try {
      clusters.getCluster("c1");
      fail("Expected to fail for non created cluster");
    }
   catch (  ClusterNotFoundException e) {
    }
    clusters.addHost("h1");
    clusters.addHost("h2");
    clusters.getHost("h1").setOsType("redhat6");
    clusters.getHost("h2").setOsType("redhat6");
    clusters.getHost("h1").persist();
    clusters.getHost("h2").persist();
    controller.createCluster(r);
    Assert.assertNotNull(clusters.getCluster("c1"));
  }
  