org.apache.hadoop.chukwa.datacollection.adaptor
Class ExecAdaptor

java.lang.Object
  org.apache.hadoop.chukwa.inputtools.plugin.ExecPlugin
      org.apache.hadoop.chukwa.datacollection.adaptor.ExecAdaptor

All Implemented Interfaces:

Adaptor, IPlugin

public class ExecAdaptor
extends ExecPlugin
implements Adaptor

Runs a command inside chukwa. Takes as params the interval in seconds at which to run the command, and the path and args to execute. Interval is optional, and defaults to 5 seconds. Example usage: add org.apache.hadoop.chukwa.datacollection.adaptor.ExecAdaptor Ps 2 /bin/ps aux 0

Field Summary

protected long

adaptorID

Fields inherited from class org.apache.hadoop.chukwa.inputtools.plugin.ExecPlugin

statusKO, statusOK

Constructor Summary

ExecAdaptor()

Method Summary

String	getCmde()
String	getCurrentStatus() Return the adaptor's state Should not include class name, datatype or byte offset, which are written by caller.
String	getStreamName() Return the stream name
String	getType()
void	hardStop() Signals this adaptor to come to an abrupt stop, as quickly as it can.
long	shutdown() Signals this adaptor to come to an orderly stop.
void	start(long adaptorID, String type, String status, long offset, ChunkReceiver dest) Start this adaptor

Methods inherited from class org.apache.hadoop.chukwa.inputtools.plugin.ExecPlugin

execute, postProcess, stop, waitFor

Methods inherited from class java.lang.Object

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

Field Detail

adaptorID

protected long adaptorID

Constructor Detail

ExecAdaptor

public ExecAdaptor()

Method Detail

getCurrentStatus

public String getCurrentStatus()
                        throws AdaptorException

Description copied from interface: Adaptor

Return the adaptor's state Should not include class name, datatype or byte offset, which are written by caller.

Specified by:

getCurrentStatus in interface Adaptor

Returns:

the adaptor state as a string

Throws:

AdaptorException

getStreamName

public String getStreamName()

Description copied from interface: Adaptor

Return the stream name

Specified by:

getStreamName in interface Adaptor

Returns:

Stream name as a string

hardStop

public void hardStop()
              throws AdaptorException

Description copied from interface: Adaptor

Signals this adaptor to come to an abrupt stop, as quickly as it can. The use case here is "Whups, I didn't mean to start that adaptor tailing a gigabyte file, stop it now". Adaptors might need to do something nontrivial here, e.g., in the case in which they have registered periodic timer interrupts, or use a shared worker thread from which they need to disengage. This method is synchronous: In other words, after shutdown() returns, no new data should be written.

Specified by:

hardStop in interface Adaptor

Throws:

AdaptorException

shutdown

public long shutdown()
              throws AdaptorException

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. This method is synchronous: In other words, after shutdown() returns, no new data should be written.

Specified by:

shutdown in interface Adaptor

Returns:

the logical offset at which the adaptor stops

Throws:

AdaptorException

start

public void start(long adaptorID,
                  String type,
                  String status,
                  long offset,
                  ChunkReceiver dest)
           throws AdaptorException

Description copied from interface: Adaptor

Start this adaptor

Specified by:

start in interface Adaptor

type - the application type, who is starting this adaptor

status - the status string to use for configuration.

offset - the stream offset of the first byte sent by this adaptor

Throws:

AdaptorException

getCmde

public String getCmde()

Specified by:

getCmde in class ExecPlugin

getType

public String getType()

Specified by:

getType in interface Adaptor