/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* 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
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators;
import java.util.ArrayList;
import java.util.List;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.plans.PhyPlanVisitor;
import org.apache.pig.backend.hadoop.executionengine.physicalLayer.plans.PhysicalPlan;
import org.apache.pig.data.DataType;
import org.apache.pig.data.Tuple;
import org.apache.pig.impl.logicalLayer.schema.Schema;
import org.apache.pig.impl.plan.OperatorKey;
import org.apache.pig.impl.plan.VisitorException;
import org.apache.pig.impl.util.MultiMap;
/**
* The PhysicalOperator that represents a skewed join. It must have two inputs.
* This operator does not do any actually work, it is only a place holder. When it is
* translated into MR plan, a POSkewedJoin is translated into a sampling job and a join
* job.
*
*
*/
public class POSkewedJoin extends PhysicalOperator {
private static final long serialVersionUID = 1L;
private boolean[] mInnerFlags;
// The schema is used only by the MRCompiler to support outer join
transient private List<Schema> inputSchema = new ArrayList<Schema>();
// physical plans to retrive join keys
// the key of this <code>MultiMap</code> is the PhysicalOperator that corresponds to an input
// the value is a list of <code>PhysicalPlan</code> to retrieve each join key for this input
private MultiMap<PhysicalOperator, PhysicalPlan> mJoinPlans;
public POSkewedJoin(OperatorKey k) {
this(k,-1,null, null);
}
public POSkewedJoin(OperatorKey k, int rp) {
this(k, rp, null, null);
}
public POSkewedJoin(OperatorKey k, List<PhysicalOperator> inp, boolean []flags) {
this(k, -1, inp, flags);
}
public POSkewedJoin(OperatorKey k, int rp, List<PhysicalOperator> inp, boolean []flags) {
super(k,rp,inp);
if (flags != null) {
// copy the inner flags
mInnerFlags = new boolean[flags.length];
for (int i = 0; i < flags.length; i++) {
mInnerFlags[i] = flags[i];
}
}
}
public boolean[] getInnerFlags() {
return mInnerFlags;
}
public MultiMap<PhysicalOperator, PhysicalPlan> getJoinPlans() {
return mJoinPlans;
}
public void setJoinPlans(MultiMap<PhysicalOperator, PhysicalPlan> joinPlans) {
mJoinPlans = joinPlans;
}
@Override
public void visit(PhyPlanVisitor v) throws VisitorException {
v.visitSkewedJoin(this);
}
@Override
public String name() {
return getAliasString() + "SkewedJoin["
+ DataType.findTypeName(resultType) + "]" + " - "
+ mKey.toString();
}
@Override
public boolean supportsMultipleInputs() {
return true;
}
@Override
public boolean supportsMultipleOutputs() {
return false;
}
public void addSchema(Schema s) {
inputSchema.add(s);
}
public Schema getSchema(int i) {
return inputSchema.get(i);
}
@Override
public Tuple illustratorMarkup(Object in, Object out, int eqClassIndex) {
return null;
}
}