org.apache.ibatis.cursor.Cursor Maven / Gradle / Ivy
/**
* Copyright 2009-2015 the original author or authors.
*
* Licensed 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.ibatis.cursor;
import java.io.Closeable;
/**
* Cursor contract to handle fetching items lazily using an Iterator.
* Cursors are a perfect fit to handle millions of items queries that would not normally fits in memory.
* Cursor SQL queries must be ordered (resultOrdered="true") using the id columns of the resultMap.
*
* @author Guillaume Darmont / [email protected]
*/
public interface Cursor extends Closeable, Iterable {
/**
* @return true if the cursor has started to fetch items from database.
*/
boolean isOpen();
/**
*
* @return true if the cursor is fully consumed and has returned all elements matching the query.
*/
boolean isConsumed();
/**
* Get the current item index. The first item has the index 0.
* @return -1 if the first cursor item has not been retrieved. The index of the current item retrieved.
*/
int getCurrentIndex();
}