org.apache.hadoop.chukwa.util

Class ConstRateAdaptor

java.lang.Object

org.apache.hadoop.chukwa.datacollection.adaptor.AbstractAdaptor

org.apache.hadoop.chukwa.util.ConstRateAdaptor

All Implemented Interfaces:

Runnable, Adaptor

public class ConstRateAdaptor
extends AbstractAdaptor
implements Runnable

Emits chunks at a roughly constant data rate. Chunks are in a very particular format: the output data is verifiable, but sufficiently non-deterministic that two different instances of this adaptor are very likely to have distinct outputs. Each chunk is full of random bytes; the randomness comes from an instance of java.util.Random seeded with the offset xored with the time-of-generation. The time of generation is stored, big-endian, in the first eight bytes of each chunk.

Field Summary

Fields inherited from class org.apache.hadoop.chukwa.datacollection.adaptor.AbstractAdaptor

adaptorID, control, dest, type

Constructor Summary

Constructors

Constructor and Description
ConstRateAdaptor()

Method Summary

Methods

Modifier and Type	Method and Description
static boolean	checkChunk(Chunk chunk)
String	getCurrentStatus() Return the adaptor's state Should not include class name or byte offset, which are written by caller.
ChunkImpl	nextChunk(int arraySize)
String	parseArgs(String bytesPerSecParam)
void	run()
long	shutdown(AdaptorShutdownPolicy shutdownPolicy) Signals this adaptor to come to an orderly stop.
void	start(long offset)
String	toString()

Methods inherited from class org.apache.hadoop.chukwa.datacollection.adaptor.AbstractAdaptor

deregisterAndStop, getType, hardStop, parseArgs, shutdown, start

Methods inherited from class java.lang.Object

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

Constructor Detail

ConstRateAdaptor

public ConstRateAdaptor()

Method Detail

getCurrentStatus

public String getCurrentStatus()

Description copied from interface: Adaptor

Return the adaptor's state Should not include class name or byte offset, which are written by caller. The datatype should, however, be written by this method.

Specified by:

getCurrentStatus in interface Adaptor

Returns:

the adaptor state as a string

start

public void start(long offset)
           throws AdaptorException

Specified by:

start in class AbstractAdaptor

Throws:

AdaptorException

parseArgs

public String parseArgs(String bytesPerSecParam)

Specified by:

parseArgs in class AbstractAdaptor

run

public void run()

Specified by:

run in interface Runnable

nextChunk

public ChunkImpl nextChunk(int arraySize)

toString

public String toString()

Overrides:

toString in class Object

shutdown

public long shutdown(AdaptorShutdownPolicy shutdownPolicy)

Description copied from interface: Adaptor

Signals this adaptor to come to an orderly stop. The adaptor ought to push out all the data it can before exiting depending of the shutdown policy

Specified by:

shutdown in interface Adaptor

Returns:

the logical offset at which the adaptor was when the method return

checkChunk

public static boolean checkChunk(Chunk chunk)