@Override
    public Double getProgress() { return source.getProgress(); }
Utility class in order to wrap com.yahoo.vespa.clustercontroller.utils.communication.async operation callbacks. Useful when translating com.yahoo.vespa.clustercontroller.utils.communication.async operations returning JSON to com.yahoo.vespa.clustercontroller.utils.communication.async operations returning specific values.
clustercontroller-utils/src/main/java/com/yahoo/vespa/clustercontroller/utils/communication/async/RedirectedAsyncOperation.java