A DeleteCalendar object requires a non-null calendarId.

DeleteCalendarRequest request = new DeleteCalendarRequest("holidays"); 

The returned AcknowledgedResponse object indicates the acknowledgement of the request:

boolean isAcknowledged = response.isAcknowledged(); 

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

AcknowledgedResponse response = client.machineLearning().deleteCalendar(request, RequestOptions.DEFAULT);

Executing a DeleteCalendarRequest 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-calendar method:

client.machineLearning().deleteCalendarAsync(request, 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-calendar looks like:

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

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