private static Set<ApplicationName> toApplications(HttpResponse<byte[]> response) {
        Set<ApplicationName> applications = new HashSet<>();
        toInspector(response).traverse((ArrayTraverser) (___, entryObject) ->
                applications.add(ApplicationName.from(entryObject.field("application").asString())));
        return applications;
    }
Returns the "message" element contained in the JSON formatted response.
hosted-api/src/main/java/ai/vespa/hosted/api/ControllerHttpClient.java