/*
* Copyright © 2014 Cask Data, Inc.
*
* 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 co.cask.cdap.data2.transaction.queue;
import co.cask.cdap.common.utils.ImmutablePair;
import java.io.IOException;
import java.util.Map;
/**
* Interface for queue scan operation.
*/
public interface QueueScanner {
ImmutablePair<byte[], Map<byte[], byte[]>> next() throws IOException;
void close() throws IOException;
QueueScanner EMPTY = new QueueScanner() {
@Override
public ImmutablePair<byte[], Map<byte[], byte[]>> next() throws IOException {
return null;
}
@Override
public void close() throws IOException {
// no-op
}
};
}