/*
* Copyright 2010 The Apache Software Foundation
* 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.hadoop.hbase.regionserver;
import java.io.IOException;
/**
* A package protected interface for a store flushing.
* A store flusher carries the state required to prepare/flush/commit the
* store's cache.
*/
interface StoreFlusher {
/**
* Prepare for a store flush (create snapshot)
*
* Requires pausing writes.
*
* A very short operation.
*/
void prepare();
/**
* Flush the cache (create the new store file)
*
* A length operation which doesn't require locking out any function
* of the store.
*
* @throws IOException in case the flush fails
*/
void flushCache() throws IOException;
/**
* Commit the flush - add the store file to the store and clear the
* memstore snapshot.
*
* Requires pausing scans.
*
* A very short operation
*
* @return
* @throws IOException
*/
boolean commit() throws IOException;
}