/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF 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.
*/
package org.apache.ignite.cache.query;
import java.util.List;
/**
* Query result cursor. Implements {@link Iterable} only for convenience, e.g. {@link #iterator()}
* can be obtained only once. Also if iteration is started then {@link #getAll()} method calls are prohibited.
*/
public interface QueryCursor<T> extends Iterable<T>, AutoCloseable {
/**
* Gets all query results and stores them in the collection.
* Use this method when you know in advance that query result is
* relatively small and will not cause memory utilization issues.
* <p>
* Since all the results will be fetched, all the resources will be closed
* automatically after this call, e.g. there is no need to call {@link #close()} method in this case.
*
* @return List containing all query results.
*/
public List<T> getAll();
/**
* Closes all resources related to this cursor. If the query execution is in progress
* (which is possible in case of invoking from another thread), a cancel will be attempted.
* Sequential calls to this method have no effect.
* <p>
* Note: don't forget to close query cursors. Not doing so may lead to various resource leaks.
*/
@Override public void close();
}