/**
* Copyright 2009 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.io.hfile;
import java.nio.ByteBuffer;
/**
* Block cache interface.
* TODO: Add filename or hash of filename to block cache key.
*/
public interface BlockCache {
/**
* Add block to cache.
* @param blockName Zero-based file block number.
* @param buf The block contents wrapped in a ByteBuffer.
* @param inMemory Whether block should be treated as in-memory
*/
public void cacheBlock(String blockName, ByteBuffer buf, boolean inMemory);
/**
* Add block to cache (defaults to not in-memory).
* @param blockName Zero-based file block number.
* @param buf The block contents wrapped in a ByteBuffer.
*/
public void cacheBlock(String blockName, ByteBuffer buf);
/**
* Fetch block from cache.
* @param blockName Block number to fetch.
* @param caching Whether this request has caching enabled (used for stats)
* @return Block or null if block is not in the cache.
*/
public ByteBuffer getBlock(String blockName, boolean caching);
/**
* Shutdown the cache.
*/
public void shutdown();
}