// Zone validation

        validateZone(zoneId);

        // Check if zone is associated with VMware DC

        if (vmwareDcZoneMap != null) {

            // Check if the associated VMware DC matches the one specified in API params

            // This check would yield success as the association exists between same entities (zone and VMware DC)

            // This scenario would result in if the API addVmwareDc is called more than once with same parameters.

            VmwareDatacenterVO associatedVmwareDc = _vmwareDcDao.findById(associatedVmwareDcId);

            if (associatedVmwareDc.getVcenterHost().equalsIgnoreCase(vCenterHost) &&

                    associatedVmwareDc.getVmwareDatacenterName().equalsIgnoreCase(vmwareDcName)) {

                s_logger.info("Ignoring API call addVmwareDc, because VMware DC " + vCenterHost + "/" + vmwareDcName +

                        " is already associated with specified zone with id " + zoneId);

                return associatedVmwareDc;

            } else {

                throw new CloudRuntimeException("Zone " + zoneId + " is already associated with a VMware datacenter. " +

                        "Only 1 VMware DC can be associated with a zone.");

            }

        }

        // Zone validation to check if the zone already has resources.

        // Association of VMware DC to zone is not allowed if zone already has resources added.

        validateZoneWithResources(zoneId, "add VMware datacenter to zone");

        // Check if DC is already part of zone

        // In that case vmware_data_center table should have the DC

        vmwareDc = _vmwareDcDao.getVmwareDatacenterByGuid(vmwareDcName + "@" + vCenterHost);

        if (vmwareDc != null) {

            throw new ResourceInUseException("This DC is already part of other CloudStack zone(s). Cannot add this DC to more zones.");

        }

        VmwareContext context = null;

        DatacenterMO dcMo = null;

        String dcCustomFieldValue;

        boolean addDcCustomFieldDef = false;

        boolean dcInUse = false;

        String guid;

        ManagedObjectReference dcMor;

        try {

            context = VmwareContextFactory.create(vCenterHost, userName, password);

            // Check if DC exists on vCenter

            dcMo = new DatacenterMO(context, vmwareDcName);

            dcMor = dcMo.getMor();

            if (dcMor == null) {

                String msg = "Unable to find VMware DC " + vmwareDcName + " in vCenter " + vCenterHost + ". ";

                s_logger.error(msg);

                throw new InvalidParameterValueException(msg);

            }

            // Check if DC is already associated with another cloudstack deployment

            // Get custom field property cloud.zone over this DC

            guid = vmwareDcName + "@" + vCenterHost;

            dcCustomFieldValue = dcMo.getCustomFieldValue(CustomFieldConstants.CLOUD_ZONE);

            if (dcCustomFieldValue == null) {

                addDcCustomFieldDef = true;

            }

            dcInUse = Boolean.parseBoolean(dcCustomFieldValue);

            if (dcInUse) {

                throw new ResourceInUseException("This DC is being managed by other CloudStack deployment. Cannot add this DC to zone.");

            }

            // Add DC to database into vmware_data_center table

            vmwareDc = new VmwareDatacenterVO(guid, vmwareDcName, vCenterHost, userName, password);

            Transaction txn = Transaction.currentTxn();

            try {

                txn.start();

                vmwareDc = _vmwareDcDao.persist(vmwareDc);

                txn.commit();

            } catch (Exception e) {

                txn.rollback();

                s_logger.error("Failed to persist VMware datacenter details to database. Exception: " + e.getMessage());

                throw new CloudRuntimeException(e.getMessage());

            }

            // Map zone with vmware datacenter

            txn = Transaction.currentTxn();

            try {

                txn.start();

                vmwareDcZoneMap = _vmwareDcZoneMapDao.persist(vmwareDcZoneMap);

                txn.commit();

            } catch (Exception e) {

                txn.rollback();

                s_logger.error("Failed to associate VMware datacenter with zone " + zoneId + ". Exception: " + e.getMessage());

                // Removing VMware datacenter from vmware_data_center table because association with zone failed.

                throw new CloudRuntimeException(e.getMessage());

            }

            // Set custom field for this DC

            if (addDcCustomFieldDef) {

        // Association of VMware DC to zone is not allowed if zone already has resources added.

        validateZoneWithResources(zoneId, "remove VMware datacenter to zone");

        // Get DC associated with this zone

        VmwareDatacenterVO vmwareDatacenter;

        String vmwareDcName;

        long vmwareDcId;

        String vCenterHost;

        String userName;

        String password;

        DatacenterMO dcMo = null;

        Transaction txn;

        vmwareDcZoneMap = _vmwareDcZoneMapDao.findByZoneId(zoneId);

        // Check if zone is associated with VMware DC

        if (vmwareDcZoneMap == null) {

            throw new CloudRuntimeException("Zone " + zoneId + " is not associated with any VMware datacenter.");

        }

        vmwareDatacenter = _vmwareDcDao.findById(vmwareDcId);

        vmwareDcName = vmwareDatacenter.getVmwareDatacenterName();

        vCenterHost = vmwareDatacenter.getVcenterHost();

        userName = vmwareDatacenter.getUser();

        password = vmwareDatacenter.getPassword();

        txn = Transaction.currentTxn();

        try {

            txn.start();

            // Remove the VMware datacenter entry in table vmware_data_center

            _vmwareDcDao.remove(vmwareDcId);

            // Remove the map entry in table vmware_data_center_zone_map

            txn.commit();

        } catch (Exception e) {

            s_logger.info("Caught exception when trying to delete VMware datacenter record." + e.getMessage());

            throw new CloudRuntimeException("Failed to delete VMware datacenter.");

        }

    @Override

    public List<? extends VmwareDatacenter> listVmwareDatacenters(ListVmwareDcsCmd cmd) throws CloudRuntimeException, InvalidParameterValueException {

        Long zoneId = cmd.getZoneId();

        List<VmwareDatacenterVO> vmwareDcList = new ArrayList<VmwareDatacenterVO>();

        VmwareDatacenterVO vmwareDatacenter;

        long vmwareDcId;

        // Validate if zone id parameter passed to API is valid

        validateZone(zoneId);

        // Check if zone is associated with VMware DC

        vmwareDcZoneMap = _vmwareDcZoneMapDao.findByZoneId(zoneId);

        if (vmwareDcZoneMap == null) {

            return null;

        }

        // Retrieve details of VMware DC associated with zone.

        vmwareDatacenter = _vmwareDcDao.findById(vmwareDcId);

        vmwareDcList.add(vmwareDatacenter);

        // Currently a zone can have only 1 VMware DC associated with.

        // Returning list of VmwareDatacenterVO objects, in-line with future requirements, if any, like participation of multiple VMware DCs in a zone.

        // Zone validation

        validateZone(zoneId);

        // Check if zone is associated with VMware DC

        if (vmwareDcZoneMap != null) {

            // Check if the associated VMware DC matches the one specified in API params

            // This check would yield success as the association exists between same entities (zone and VMware DC)

            // This scenario would result in if the API addVmwareDc is called more than once with same parameters.

            VmwareDatacenterVO associatedVmwareDc = _vmwareDcDao.findById(associatedVmwareDcId);

            if (associatedVmwareDc.getVcenterHost().equalsIgnoreCase(vCenterHost) &&

                    associatedVmwareDc.getVmwareDatacenterName().equalsIgnoreCase(vmwareDcName)) {

                s_logger.info("Ignoring API call addVmwareDc, because VMware DC " + vCenterHost + "/" + vmwareDcName +

                        " is already associated with specified zone with id " + zoneId);

                return associatedVmwareDc;

            } else {

                throw new CloudRuntimeException("Zone " + zoneId + " is already associated with a VMware datacenter. " +

                        "Only 1 VMware DC can be associated with a zone.");

            }

        }

        // Zone validation to check if the zone already has resources.

        // Association of VMware DC to zone is not allowed if zone already has resources added.

        validateZoneWithResources(zoneId, "add VMware datacenter to zone");

        // Check if DC is already part of zone

        // In that case vmware_data_center table should have the DC

        vmwareDc = _vmwareDcDao.getVmwareDatacenterByGuid(vmwareDcName + "@" + vCenterHost);

        if (vmwareDc != null) {

            throw new ResourceInUseException("This DC is already part of other CloudStack zone(s). Cannot add this DC to more zones.");

        }

        VmwareContext context = null;

        DatacenterMO dcMo = null;

        String dcCustomFieldValue;

        boolean addDcCustomFieldDef = false;

        boolean dcInUse = false;

        String guid;

        ManagedObjectReference dcMor;

        try {

            context = VmwareContextFactory.create(vCenterHost, userName, password);

            // Check if DC exists on vCenter

            dcMo = new DatacenterMO(context, vmwareDcName);

            dcMor = dcMo.getMor();

            if (dcMor == null) {

                String msg = "Unable to find VMware DC " + vmwareDcName + " in vCenter " + vCenterHost + ". ";

                s_logger.error(msg);

                throw new InvalidParameterValueException(msg);

            }

            // Check if DC is already associated with another cloudstack deployment

            // Get custom field property cloud.zone over this DC

            guid = vmwareDcName + "@" + vCenterHost;

            dcCustomFieldValue = dcMo.getCustomFieldValue(CustomFieldConstants.CLOUD_ZONE);

            if (dcCustomFieldValue == null) {

                addDcCustomFieldDef = true;

            }

            dcInUse = Boolean.parseBoolean(dcCustomFieldValue);

            if (dcInUse) {

                throw new ResourceInUseException("This DC is being managed by other CloudStack deployment. Cannot add this DC to zone.");

            }

            // Add DC to database into vmware_data_center table

            vmwareDc = new VmwareDatacenterVO(guid, vmwareDcName, vCenterHost, userName, password);

            vmwareDc = _vmwareDcDao.persist(vmwareDc);

            // Map zone with vmware datacenter

            vmwareDcZoneMap = _vmwareDcZoneMapDao.persist(vmwareDcZoneMap);

            // Set custom field for this DC

            if (addDcCustomFieldDef) {

        String password;

        DatacenterMO dcMo = null;

        Transaction txn;

        // Check if zone is associated with VMware DC

        if (vmwareDcZoneMap == null) {

            throw new CloudRuntimeException("Zone " + zoneId + " is not associated with any VMware datacenter.");

        }

        vmwareDatacenter = _vmwareDcDao.findById(vmwareDcId);

        vmwareDcName = vmwareDatacenter.getVmwareDatacenterName();

        vCenterHost = vmwareDatacenter.getVcenterHost();

        userName = vmwareDatacenter.getUser();

        password = vmwareDatacenter.getPassword();

        Transaction.execute(new TransactionCallbackNoReturn() {

            @Override

            public void doInTransactionWithoutResult(TransactionStatus status) {

                // Remove the VMware datacenter entry in table vmware_data_center

                _vmwareDcDao.remove(vmwareDcId);

                // Remove the map entry in table vmware_data_center_zone_map

            }

        });

        // Construct context

        VmwareContext context = null;

    @Override

    public List<? extends VmwareDatacenter> listVmwareDatacenters(ListVmwareDcsCmd cmd) throws CloudRuntimeException, InvalidParameterValueException {

        Long zoneId = cmd.getZoneId();

        List<VmwareDatacenterVO> vmwareDcList = new ArrayList<VmwareDatacenterVO>();

        VmwareDatacenterVO vmwareDatacenter;

        long vmwareDcId;

        // Validate if zone id parameter passed to API is valid

        validateZone(zoneId);

        // Check if zone is associated with VMware DC

        vmwareDcZoneMap = _vmwareDcZoneMapDao.findByZoneId(zoneId);

        if (vmwareDcZoneMap == null) {

            return null;

        }

        // Retrieve details of VMware DC associated with zone.

        vmwareDatacenter = _vmwareDcDao.findById(vmwareDcId);

        vmwareDcList.add(vmwareDatacenter);

        // Currently a zone can have only 1 VMware DC associated with.

        // Returning list of VmwareDatacenterVO objects, in-line with future requirements, if any, like participation of multiple VMware DCs in a zone.

        // Zone validation

        validateZone(zoneId);

        // Check if zone is associated with VMware DC

        if (vmwareDcZoneMap != null) {

            // Check if the associated VMware DC matches the one specified in API params

            // This check would yield success as the association exists between same entities (zone and VMware DC)

            // This scenario would result in if the API addVmwareDc is called more than once with same parameters.

            VmwareDatacenterVO associatedVmwareDc = _vmwareDcDao.findById(associatedVmwareDcId);

            if (associatedVmwareDc.getVcenterHost().equalsIgnoreCase(vCenterHost) && associatedVmwareDc.getVmwareDatacenterName().equalsIgnoreCase(vmwareDcName)) {

                s_logger.info("Ignoring API call addVmwareDc, because VMware DC " + vCenterHost + "/" + vmwareDcName +

                        " is already associated with specified zone with id " + zoneId);

                return associatedVmwareDc;

            } else {

                throw new CloudRuntimeException("Zone " + zoneId + " is already associated with a VMware datacenter. " +

                        "Only 1 VMware DC can be associated with a zone.");

            }

        }

        // Zone validation to check if the zone already has resources.

        // Association of VMware DC to zone is not allowed if zone already has resources added.

        validateZoneWithResources(zoneId, "add VMware datacenter to zone");

        // Check if DC is already part of zone

        // In that case vmware_data_center table should have the DC

        vmwareDc = _vmwareDcDao.getVmwareDatacenterByGuid(vmwareDcName + "@" + vCenterHost);

        if (vmwareDc != null) {

            throw new ResourceInUseException("This DC is already part of other CloudStack zone(s). Cannot add this DC to more zones.");

        }

        VmwareContext context = null;

        DatacenterMO dcMo = null;

        String dcCustomFieldValue;

        boolean addDcCustomFieldDef = false;

        boolean dcInUse = false;

        String guid;

        ManagedObjectReference dcMor;

        try {

            context = VmwareContextFactory.create(vCenterHost, userName, password);

            // Check if DC exists on vCenter

            dcMo = new DatacenterMO(context, vmwareDcName);

            dcMor = dcMo.getMor();

            if (dcMor == null) {

                String msg = "Unable to find VMware DC " + vmwareDcName + " in vCenter " + vCenterHost + ". ";

                s_logger.error(msg);

                throw new InvalidParameterValueException(msg);

            }

            // Check if DC is already associated with another cloudstack deployment

            // Get custom field property cloud.zone over this DC

            guid = vmwareDcName + "@" + vCenterHost;

            dcCustomFieldValue = dcMo.getCustomFieldValue(CustomFieldConstants.CLOUD_ZONE);

            if (dcCustomFieldValue == null) {

                addDcCustomFieldDef = true;

            }

            dcInUse = Boolean.parseBoolean(dcCustomFieldValue);

            if (dcInUse) {

                throw new ResourceInUseException("This DC is being managed by other CloudStack deployment. Cannot add this DC to zone.");

            }

            // Add DC to database into vmware_data_center table

            vmwareDc = new VmwareDatacenterVO(guid, vmwareDcName, vCenterHost, userName, password);

            vmwareDc = _vmwareDcDao.persist(vmwareDc);

            // Map zone with vmware datacenter

            vmwareDcZoneMap = _vmwareDcZoneMapDao.persist(vmwareDcZoneMap);

            // Set custom field for this DC

            if (addDcCustomFieldDef) {

        String vCenterHost;

        String userName;

        String password;

        DatacenterMO dcMo = null;

        // Check if zone is associated with VMware DC

        if (vmwareDcZoneMap == null) {

            throw new CloudRuntimeException("Zone " + zoneId + " is not associated with any VMware datacenter.");

        }

        vmwareDatacenter = _vmwareDcDao.findById(vmwareDcId);

        vmwareDcName = vmwareDatacenter.getVmwareDatacenterName();

        vCenterHost = vmwareDatacenter.getVcenterHost();

        userName = vmwareDatacenter.getUser();

        password = vmwareDatacenter.getPassword();

        Transaction.execute(new TransactionCallbackNoReturn() {

            @Override

            public void doInTransactionWithoutResult(TransactionStatus status) {

                // Remove the VMware datacenter entry in table vmware_data_center

                _vmwareDcDao.remove(vmwareDcId);

                // Remove the map entry in table vmware_data_center_zone_map

            }

        });

        // Construct context

        VmwareContext context = null;

    @Override

    public List<? extends VmwareDatacenter> listVmwareDatacenters(ListVmwareDcsCmd cmd) throws CloudRuntimeException, InvalidParameterValueException {

        Long zoneId = cmd.getZoneId();

        List<VmwareDatacenterVO> vmwareDcList = new ArrayList<VmwareDatacenterVO>();

        VmwareDatacenterVO vmwareDatacenter;

        long vmwareDcId;

        // Validate if zone id parameter passed to API is valid

        validateZone(zoneId);

        // Check if zone is associated with VMware DC

        vmwareDcZoneMap = _vmwareDcZoneMapDao.findByZoneId(zoneId);

        if (vmwareDcZoneMap == null) {

            return null;

        }

        // Retrieve details of VMware DC associated with zone.

        vmwareDatacenter = _vmwareDcDao.findById(vmwareDcId);

        vmwareDcList.add(vmwareDatacenter);

        // Currently a zone can have only 1 VMware DC associated with.

        // Returning list of VmwareDatacenterVO objects, in-line with future requirements, if any, like participation of multiple VMware DCs in a zone.

        // Zone validation

        validateZone(zoneId);

        // Check if zone is associated with VMware DC

        if (vmwareDcZoneMap != null) {

            // Check if the associated VMware DC matches the one specified in API params

            // This check would yield success as the association exists between same entities (zone and VMware DC)

            // This scenario would result in if the API addVmwareDc is called more than once with same parameters.

            VmwareDatacenterVO associatedVmwareDc = _vmwareDcDao.findById(associatedVmwareDcId);

            if (associatedVmwareDc.getVcenterHost().equalsIgnoreCase(vCenterHost) &&

                    associatedVmwareDc.getVmwareDatacenterName().equalsIgnoreCase(vmwareDcName)) {

                s_logger.info("Ignoring API call addVmwareDc, because VMware DC " + vCenterHost + "/" + vmwareDcName +

                        " is already associated with specified zone with id " + zoneId);

                return associatedVmwareDc;

            } else {

                throw new CloudRuntimeException("Zone " + zoneId + " is already associated with a VMware datacenter. " +

                        "Only 1 VMware DC can be associated with a zone.");

            }

        }

        // Zone validation to check if the zone already has resources.

        // Association of VMware DC to zone is not allowed if zone already has resources added.

        validateZoneWithResources(zoneId, "add VMware datacenter to zone");

        // Check if DC is already part of zone

        // In that case vmware_data_center table should have the DC

        vmwareDc = _vmwareDcDao.getVmwareDatacenterByGuid(vmwareDcName + "@" + vCenterHost);

        if (vmwareDc != null) {

            throw new ResourceInUseException("This DC is already part of other CloudStack zone(s). Cannot add this DC to more zones.");

        }

        VmwareContext context = null;

        DatacenterMO dcMo = null;

        String dcCustomFieldValue;

        boolean addDcCustomFieldDef = false;

        boolean dcInUse = false;

        String guid;

        ManagedObjectReference dcMor;

        try {

            context = VmwareContextFactory.create(vCenterHost, userName, password);

            // Check if DC exists on vCenter

            dcMo = new DatacenterMO(context, vmwareDcName);

            dcMor = dcMo.getMor();

            if (dcMor == null) {

                String msg = "Unable to find VMware DC " + vmwareDcName + " in vCenter " + vCenterHost + ". ";

                s_logger.error(msg);

                throw new InvalidParameterValueException(msg);

            }

            // Check if DC is already associated with another cloudstack deployment

            // Get custom field property cloud.zone over this DC

            guid = vmwareDcName + "@" + vCenterHost;

            dcCustomFieldValue = dcMo.getCustomFieldValue(CustomFieldConstants.CLOUD_ZONE);

            if (dcCustomFieldValue == null) {

                addDcCustomFieldDef = true;

            }

            dcInUse = Boolean.parseBoolean(dcCustomFieldValue);

            if (dcInUse) {

                throw new ResourceInUseException("This DC is being managed by other CloudStack deployment. Cannot add this DC to zone.");

            }

            // Add DC to database into vmware_data_center table

            vmwareDc = new VmwareDatacenterVO(guid, vmwareDcName, vCenterHost, userName, password);

            Transaction txn = Transaction.currentTxn();

            try {

                txn.start();

                vmwareDc = _vmwareDcDao.persist(vmwareDc);

                txn.commit();

            } catch (Exception e) {

                txn.rollback();

                s_logger.error("Failed to persist VMware datacenter details to database. Exception: " + e.getMessage());

                throw new CloudRuntimeException(e.getMessage());

            }

            // Map zone with vmware datacenter

            txn = Transaction.currentTxn();

            try {

                txn.start();

                vmwareDcZoneMap = _vmwareDcZoneMapDao.persist(vmwareDcZoneMap);

                txn.commit();

            } catch (Exception e) {

                txn.rollback();

                s_logger.error("Failed to associate VMware datacenter with zone " + zoneId + ". Exception: " + e.getMessage());

                // Removing VMware datacenter from vmware_data_center table because association with zone failed.

                throw new CloudRuntimeException(e.getMessage());

            }

            // Set custom field for this DC

            if (addDcCustomFieldDef) {