allows extensions to prevent a cloud from provisioning . return null to allow provisioning , or non-null to prevent it . concode_field_sep PlaceHolder placeHolder concode_field_sep ExtensionList<CloudProvisioningListener> all concode_elem_sep void onStarted concode_elem_sep void onComplete concode_elem_sep void onFailure
CauseOfBlockage function ( Cloud arg0 , Label arg1 , int arg2 ) { return null ; }