/*
* Licensed to Crate.IO GmbH ("Crate") under one or more contributor
* license agreements. See the NOTICE file distributed with this work for
* additional information regarding copyright ownership. Crate licenses
* this file to you under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License. You may
* obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
* However, if you have executed another commercial license agreement
* with Crate these terms will supersede the license and you may use the
* software solely pursuant to the terms of the relevant commercial agreement.
*/
package io.crate.operation.merge;
import java.util.Iterator;
public interface PagingIterator<TKey, TRow> extends Iterator<TRow> {
/**
* Add additional iterables to the PagingIterator. (E.g. due to a new Page that has arrived)
*/
void merge(Iterable<? extends KeyIterable<TKey, TRow>> iterables);
/**
* This is called if the last page has been received and merge has been called for the last time.
* If the PagingIterator implementation has been holding rows back, these rows should now be
* returned on hasNext/next calls.
*/
void finish();
TKey exhaustedIterable();
/**
* create an iterable to repeat the previous iteration
*
* @return an iterable that will iterate through the already emitted items and emit them again in the same order as before
*/
Iterable<TRow> repeat();
}