Package org.apache.hadoop.hbase.io.hfile.bucket

Class ExclusiveMemoryMmapIOEngine

java.lang.Object

org.apache.hadoop.hbase.io.hfile.bucket.PersistentIOEngine

org.apache.hadoop.hbase.io.hfile.bucket.FileMmapIOEngine

org.apache.hadoop.hbase.io.hfile.bucket.ExclusiveMemoryMmapIOEngine

All Implemented Interfaces:

IOEngine

@Private
public class ExclusiveMemoryMmapIOEngine
extends FileMmapIOEngine

IO engine that stores data to a file on the local block device using memory mapping mechanism

Field Summary

Fields inherited from class org.apache.hadoop.hbase.io.hfile.bucket.FileMmapIOEngine

bufferArray, LOG, path, size

Fields inherited from class org.apache.hadoop.hbase.io.hfile.bucket.PersistentIOEngine

filePaths

Constructor Summary

Constructors

Constructor	Description
ExclusiveMemoryMmapIOEngine(String filePath, long capacity)

Method Summary

Modifier and Type	Method	Description
Cacheable	read(BucketEntry be)	Transfers data from IOEngine to a Cacheable object.

Methods inherited from class org.apache.hadoop.hbase.io.hfile.bucket.FileMmapIOEngine

isPersistent, shutdown, sync, toString, write, write

Methods inherited from class org.apache.hadoop.hbase.io.hfile.bucket.PersistentIOEngine

calculateChecksum, verifyFileIntegrity

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.hadoop.hbase.io.hfile.bucket.IOEngine

usesSharedMemory

Constructor Details

ExclusiveMemoryMmapIOEngine

public ExclusiveMemoryMmapIOEngine(String filePath,
 long capacity)
                            throws IOException

Throws:

IOException

Method Details

read

public Cacheable read(BucketEntry be)
               throws IOException

Description copied from interface: IOEngine

Transfers data from IOEngine to a Cacheable object.

Specified by:

read in interface IOEngine

Specified by:

read in class FileMmapIOEngine

Parameters:

be - maintains an (offset,len,refCnt) inside.

Returns:

Cacheable which will wrap the NIO ByteBuffers from IOEngine.

Throws:

IOException - when any IO error happen