/**
* 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.hdfs.server.blockmanagement;
import java.io.IOException;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.fs.ContentSummary;
/**
* This interface is used by the block manager to expose a
* few characteristics of a collection of Block/BlockUnderConstruction.
*/
@InterfaceAudience.Private
public interface BlockCollection {
/**
* Get the last block of the collection.
*/
public BlockInfo getLastBlock() throws IOException;
/**
* Get content summary.
*/
public ContentSummary computeContentSummary();
/**
* @return the number of blocks
*/
public int numBlocks();
/**
* Get the blocks.
*/
public BlockInfo[] getBlocks();
/**
* Get preferred block size for the collection
* @return preferred block size in bytes
*/
public long getPreferredBlockSize();
/**
* Get block replication for the collection
* @return block replication value
*/
public short getBlockReplication();
/**
* Get the name of the collection.
*/
public String getName();
}