A DeleteDatafeedRequest object requires a non-null datafeedId and can optionally set force.

DeleteDatafeedRequest deleteDatafeedRequest = new DeleteDatafeedRequest(datafeedId);
deleteDatafeedRequest.setForce(false); 

When executing a DeleteDatafeedRequest in the following manner, the client waits for the AcknowledgedResponse to be returned before continuing with code execution:

AcknowledgedResponse deleteDatafeedResponse = client.machineLearning().deleteDatafeed(
    deleteDatafeedRequest, RequestOptions.DEFAULT);

Executing a DeleteDatafeedRequest can also be done in an asynchronous fashion so that the client can return directly. Users need to specify how the response or potential failures will be handled by passing the request and a listener to the asynchronous delete-datafeed method:

client.machineLearning().deleteDatafeedAsync(deleteDatafeedRequest, RequestOptions.DEFAULT, listener); 

The asynchronous method does not block and returns immediately. Once it is completed the ActionListener is called back using the onResponse method if the execution successfully completed or using the onFailure method if it failed.

A typical listener for delete-datafeed looks like:

ActionListener<AcknowledgedResponse> listener = new ActionListener<AcknowledgedResponse>() {
    @Override
    public void onResponse(AcknowledgedResponse acknowledgedResponse) {
        
    }

    @Override
    public void onFailure(Exception e) {
        
    }
};

The returned AcknowledgedResponse object indicates the acknowledgement of the request:

boolean isAcknowledged = deleteDatafeedResponse.isAcknowledged();