org.apache.pig.backend.hadoop.executionengine.fetch
Class FetchLauncher

java.lang.Object
  org.apache.pig.backend.hadoop.executionengine.fetch.FetchLauncher

public class FetchLauncher
extends Object

This class is responsible for executing the fetch task, saving the result to disk and do the necessary cleanup afterwards.

Constructor Summary

FetchLauncher(PigContext pigContext)

Method Summary

void	explain(PhysicalPlan pp, PigContext pc, PrintStream ps, String format) Creates an empty MR plan
PigStats	launchPig(PhysicalPlan pp) Runs the fetch task by executing chain of calls on the PhysicalPlan from the leaf up to the LoadFunc

Methods inherited from class java.lang.Object

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

Constructor Detail

FetchLauncher

public FetchLauncher(PigContext pigContext)

Method Detail

launchPig

public PigStats launchPig(PhysicalPlan pp)
                   throws IOException

Runs the fetch task by executing chain of calls on the PhysicalPlan from the leaf up to the LoadFunc

Parameters:

pp - - Physical plan

Returns:

SimpleFetchPigStats instance representing the fetched result

Throws:

IOException

explain

public void explain(PhysicalPlan pp,
                    PigContext pc,
                    PrintStream ps,
                    String format)
             throws PlanException,
                    VisitorException,
                    IOException

Creates an empty MR plan

Parameters:

pp - - Physical plan

pc - - PigContext

ps - - PrintStream to write the plan to

format - format of the output plan

Throws:

PlanException

VisitorException

IOException