public void setRegions(java.util.Collection<String> regions) {
        if (regions == null) {
            this.regions = null;
            return;
        }

        this.regions = new com.amazonaws.internal.SdkInternalList<String>(regions);
    }
<p>
The Amazon Web Services Regions where you want to delete stack set instances.
</p>

@param regions
       The Amazon Web Services Regions where you want to delete stack set instances.
aws-java-sdk-cloudformation/src/main/java/com/amazonaws/services/cloudformation/model/DeleteStackInstancesRequest.java