com.datastax.driver.core.AsyncContinuousPagingResult Maven / Gradle / Ivy
/*
* Copyright DataStax, Inc.
*
* This software can be used solely with DataStax Enterprise. Please consult the license at
* http://www.datastax.com/terms/datastax-dse-driver-license-terms
*/
package com.datastax.driver.core;
import com.google.common.util.concurrent.ListenableFuture;
/**
* The result of an {@link ContinuousPagingSession#executeContinuouslyAsync(Statement,
* ContinuousPagingOptions) asynchronous continuous paging query}.
*
* DSE replies to a continuous query with a stream of response frames. There is one instance of
* this class for each frame.
*/
public interface AsyncContinuousPagingResult {
/**
* Returns an iterable of the rows in the current page.
*
*
More results might be available via {@link #nextPage()}.
*/
Iterable currentPage();
/** Indicates if this is the last page in the stream of results. */
boolean isLast();
/**
* Returns a future wrapping the next page in the stream of results.
*
* This will return a failed future for the last page; you should always check {@link
* #isLast()} before calling this method.
*/
ListenableFuture nextPage();
/** Returns the definition of the columns returned in this result set. */
ColumnDefinitions getColumnDefinitions();
/** Returns the page number. */
int pageNumber();
/**
* Cancels the continuous query.
*
* The driver will send an additional request to ask DSE to stop sending results. Because that
* request is asynchronous (and because the driver caches pages locally), there will probably be
* more pages available (via {@link #nextPage()}) after a call to this method. However, note that
* the server does not set {@link #isLast()} after a cancellation, so there is no reliable way to
* detect how many of these remaining pages are left.
*/
void cancel();
/**
* Returns information on the execution of the query, and on the response frame used to build this
* result.
*
*
In particular, it contains the paging state for the current page.
*
*
The driver does not support query traces for continuous queries, the corresponding field
* will always be {@code null}.
*/
ExecutionInfo getExecutionInfo();
}