/*
* 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.geode.cache.snapshot;
import java.io.IOException;
import java.util.NoSuchElementException;
import java.util.Map.Entry;
/**
* Iterates over the entries in a region snapshot. Holds resources that must be freed via
* {@link #close()}.
*
* @param <K> the key type of the snapshot region
* @param <V> the value type the snapshot region
*
* @see SnapshotReader
*
* @since GemFire 7.0
*/
public interface SnapshotIterator<K, V> {
/**
* Returns true if there are more elements in the iteration.
*
* @return true if the iterator has more elements.
*
* @throws IOException error reading the snapshot
* @throws ClassNotFoundException error deserializing the snapshot element
*/
boolean hasNext() throws IOException, ClassNotFoundException;
/**
* Returns the next element in the iteration.
*
* @return the next element
*
* @throws NoSuchElementException there are no further elements
* @throws IOException error reading the snapshot
* @throws ClassNotFoundException error deserializing the snapshot element
*/
Entry<K, V> next() throws IOException, ClassNotFoundException;
/**
* Closes the iterator and its underlying resources.
*
* @throws IOException error closing the iterator
*/
void close() throws IOException;
}