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* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
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package org.apache.pig.backend.hadoop.executionengine.mapReduceLayer;
import java.util.ArrayList;
import java.util.List;
import org.apache.pig.PigException;
import org.apache.pig.backend.executionengine.ExecException;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.POProject;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.plans.PhysicalPlan;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POForEach;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POLocalRearrange;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POPackage;
import org.apache.pig.data.DataType;
import org.apache.pig.impl.plan.NodeIdGenerator;
import org.apache.pig.impl.plan.OperatorKey;
import org.apache.pig.impl.plan.PlanException;
public class MRUtil {
// simpleConnectMapToReduce is a utility to end a map phase and start a reduce phase in
// a mapreduce operator:
// 1. mro only contains map plan
// 2. need to add POLocalRearrange to end map plan, and add
// POPackage to start a reduce plan
// 3. POLocalRearrange/POPackage are trivial
static public void simpleConnectMapToReduce(MapReduceOper mro, String scope, NodeIdGenerator nig) throws PlanException
{
PhysicalPlan ep = new PhysicalPlan();
POProject prjStar = new POProject(new OperatorKey(scope,nig.getNextNodeId(scope)));
prjStar.setResultType(DataType.TUPLE);
prjStar.setStar(true);
ep.add(prjStar);
List<PhysicalPlan> eps = new ArrayList<PhysicalPlan>();
eps.add(ep);
POLocalRearrange lr = new POLocalRearrange(new OperatorKey(scope,nig.getNextNodeId(scope)));
try {
lr.setIndex(0);
} catch (ExecException e) {
int errCode = 2058;
String msg = "Unable to set index on the newly created POLocalRearrange.";
throw new PlanException(msg, errCode, PigException.BUG, e);
}
lr.setKeyType(DataType.TUPLE);
lr.setPlans(eps);
lr.setResultType(DataType.TUPLE);
mro.mapPlan.addAsLeaf(lr);
POPackage pkg = new POPackage(new OperatorKey(scope,nig.getNextNodeId(scope)));
pkg.getPkgr().setKeyType(DataType.TUPLE);
pkg.setNumInps(1);
boolean[] inner = {false};
pkg.getPkgr().setInner(inner);
mro.reducePlan.add(pkg);
mro.reducePlan.addAsLeaf(getPlainForEachOP(scope, nig));
}
// Get a simple POForEach: ForEach X generate flatten($1)
static public POForEach getPlainForEachOP(String scope, NodeIdGenerator nig)
{
List<PhysicalPlan> eps1 = new ArrayList<PhysicalPlan>();
List<Boolean> flat1 = new ArrayList<Boolean>();
PhysicalPlan ep1 = new PhysicalPlan();
POProject prj1 = new POProject(new OperatorKey(scope,nig.getNextNodeId(scope)));
prj1.setResultType(DataType.TUPLE);
prj1.setStar(false);
prj1.setColumn(1);
prj1.setOverloaded(true);
ep1.add(prj1);
eps1.add(ep1);
flat1.add(true);
POForEach fe = new POForEach(new OperatorKey(scope, nig
.getNextNodeId(scope)), -1, eps1, flat1);
fe.setResultType(DataType.BAG);
return fe;
}
}