public VmwareCloudImage(
      @NotNull final VMWareApiConnector apiConnector,
      @NotNull final VmwareCloudImageDetails imageDetails,
      @NotNull final CloudAsyncTaskExecutor asyncTaskExecutor,
      @NotNull final File idxStorage) {
    super(imageDetails.getNickname(), imageDetails.getNickname());
    myImageDetails = imageDetails;
    myApiConnector = apiConnector;
    myAsyncTaskExecutor = asyncTaskExecutor;
    myInstances.clear();
    myIdxFile = new File(idxStorage, imageDetails.getNickname() + ".idx");
    if (!myIdxFile.exists()) {
      try {
        FileUtil.writeFileAndReportErrors(myIdxFile, "1");
      } catch (IOException e) {
        LOG.warn(
            String.format(
                "Unable to write idx file '%s': %s", myIdxFile.getAbsolutePath(), e.toString()));
      }
    }

    Map<String, VmwareInstance> realInstances = null;
    try {
      realInstances = myApiConnector.listImageInstances(this);
    } catch (VmwareCheckedCloudException e) {
      updateErrors(TypedCloudErrorInfo.fromException(e));
      return;
    }
    if (imageDetails.getBehaviour().isUseOriginal()) {
      final VmwareCloudInstance imageInstance =
          new VmwareCloudInstance(
              this, imageDetails.getSourceName(), VmwareConstants.CURRENT_STATE);
      myInstances.put(myImageDetails.getSourceName(), imageInstance);

      final VmwareInstance vmwareInstance = realInstances.get(imageDetails.getSourceName());
      if (vmwareInstance != null) {
        imageInstance.setStatus(vmwareInstance.getInstanceStatus());
      } else {
        imageInstance.setStatus(InstanceStatus.UNKNOWN);
        imageInstance.updateErrors(
            new TypedCloudErrorInfo("NoVM", "VM doesn't exist: " + imageDetails.getSourceName()));
      }
    } else {
      for (String instanceName : realInstances.keySet()) {
        final VmwareInstance instance = realInstances.get(instanceName);
        final String snapshotName = instance.getSnapshotName();
        VmwareCloudInstance cloudInstance =
            new VmwareCloudInstance(this, instanceName, snapshotName);
        cloudInstance.setStatus(instance.getInstanceStatus());
        myInstances.put(instanceName, cloudInstance);
      }
    }
  }
  @NotNull
  protected synchronized VmwareCloudInstance getOrCreateInstance()
      throws VmwareCheckedCloudException {
    if (!canStartNewInstance()) {
      throw new QuotaException("Unable to start more instances of image " + getName());
    }

    if (myImageDetails.getBehaviour().isUseOriginal()) {
      LOG.info("Won't create a new instance - using original");
      return myInstances.get(myImageDetails.getSourceName());
    }

    final String latestSnapshotName =
        myApiConnector.getLatestSnapshot(
            myImageDetails.getSourceName(), myImageDetails.getSnapshotName());
    if (!myImageDetails.useCurrentVersion() && latestSnapshotName == null) {
      updateErrors(new TypedCloudErrorInfo("No such snapshot: " + getSnapshotName()));
      throw new VmwareCheckedCloudException(
          "Unable to find snapshot: " + myImageDetails.getSnapshotName());
    }

    if (!myImageDetails.getBehaviour().isDeleteAfterStop()) {
      // on demand clone
      final Map<String, VmwareInstance> vmClones = myApiConnector.listImageInstances(this);

      // start an existsing one.
      final VmwareInstance imageVm =
          myApiConnector.getInstanceDetails(myImageDetails.getSourceName());
      for (VmwareInstance vmInstance : vmClones.values()) {
        if (vmInstance.getInstanceStatus() == InstanceStatus.STOPPED) {

          final String vmName = vmInstance.getName();
          final VmwareCloudInstance instance = myInstances.get(vmName);

          if (instance == null) {
            LOG.warn("Unable to find instance " + vmName + " in myInstances.");
            continue;
          }

          // checking if this instance is already starting.
          if (instance.getStatus() != InstanceStatus.STOPPED) continue;

          if (myImageDetails.useCurrentVersion()) {
            if (imageVm.getChangeVersion() == null
                || !imageVm.getChangeVersion().equals(vmInstance.getChangeVersion())) {
              LOG.info(
                  String.format(
                      "Change version for %s is outdated: '%s' vs '%s'",
                      vmName, vmInstance.getChangeVersion(), imageVm.getChangeVersion()));
              deleteInstance(instance);
              continue;
            }
          } else {
            final String snapshotName = vmInstance.getSnapshotName();
            if (latestSnapshotName != null && !latestSnapshotName.equals(snapshotName)) {
              LOG.info(
                  String.format(
                      "VM %s Snapshot is not the latest one: '%s' vs '%s'",
                      vmName, snapshotName, latestSnapshotName));
              deleteInstance(instance);
              continue;
            }
          }
          LOG.info("Will use existing VM with name " + vmName);
          return instance;
        }
      }
    }
    // wasn't able to find an existing candidate, so will clone into a new VM
    final String newVmName = generateNewVmName();
    LOG.info("Will create a new VM with name " + newVmName);
    return new VmwareCloudInstance(this, newVmName, latestSnapshotName);
  }