org.apache.giraph.ooc.command

Class IOCommand

java.lang.Object

org.apache.giraph.ooc.command.IOCommand

Direct Known Subclasses:

LoadPartitionIOCommand, StoreDataBufferIOCommand, StoreIncomingMessageIOCommand, StorePartitionIOCommand, WaitIOCommand

public abstract class IOCommand
extends Object

Representation of an IO command (moving data to disk/memory) used in out-of-core mechanism.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	IOCommand.IOCommandType Type of IO command

Field Summary

Fields

Modifier and Type	Field and Description
protected long	numBytesTransferred Number of bytes transferred to/from memory (loaded/stored) during the execution of the command
protected OutOfCoreEngine	oocEngine Out-of-core engine
protected int	partitionId Id of the partition involved for the IO

Constructor Summary

Constructors

Constructor and Description
IOCommand(OutOfCoreEngine oocEngine, int partitionId) Constructor

Method Summary

Modifier and Type	Method and Description
long	bytesTransferred() Get the number of bytes transferred (loaded/stored from/to disk).
abstract boolean	execute() Execute (load/store of data) the IO command, and change the data stores appropriately based on the data loaded/stored.
int	getPartitionId() Get the id of the partition involved in the IO
abstract IOCommand.IOCommandType	getType() Get the type of the command.

Methods inherited from class java.lang.Object

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

Field Detail

partitionId

protected final int partitionId

Id of the partition involved for the IO

oocEngine

protected final OutOfCoreEngine oocEngine

Out-of-core engine

numBytesTransferred

protected long numBytesTransferred

Number of bytes transferred to/from memory (loaded/stored) during the execution of the command

Constructor Detail

IOCommand

public IOCommand(OutOfCoreEngine oocEngine,
                 int partitionId)

Constructor

Parameters:

oocEngine - Out-of-core engine

partitionId - Id of the partition involved in the IO

Method Detail

getPartitionId

public int getPartitionId()

Get the id of the partition involved in the IO

Returns:

id of the partition

execute

public abstract boolean execute()
                         throws IOException

Execute (load/store of data) the IO command, and change the data stores appropriately based on the data loaded/stored. Return true iff the command is actually executed (resulted in loading or storing data).

Returns:

whether the command is actually executed

Throws:

IOException

getType

public abstract IOCommand.IOCommandType getType()

Get the type of the command.

Returns:

type of the command

bytesTransferred

public long bytesTransferred()

Get the number of bytes transferred (loaded/stored from/to disk).

Returns:

number of bytes transferred during the execution of the command