| /* |
| * 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.List; |
| |
| import org.apache.pig.backend.executionengine.ExecException; |
| import org.apache.pig.backend.hadoop.executionengine.physicalLayer.POStatus; |
| import org.apache.pig.backend.hadoop.executionengine.physicalLayer.Result; |
| 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.impl.plan.OperatorKey; |
| import org.apache.pig.impl.plan.VisitorException; |
| |
| /** |
| * A specialized version of POForeach with the difference |
| * that in getNext(), it knows that "input" has already been |
| * attached by its input operator which SHOULD be POJoinPackage |
| */ |
| |
| //We intentionally skip type checking in backend for performance reasons |
| @SuppressWarnings("unchecked") |
| public class POOptimizedForEach extends POForEach { |
| |
| /** |
| * |
| */ |
| private static final long serialVersionUID = 1L; |
| |
| public POOptimizedForEach(OperatorKey k) { |
| this(k,-1,null,null); |
| } |
| |
| public POOptimizedForEach(OperatorKey k, int rp, List inp) { |
| this(k,rp,inp,null); |
| } |
| |
| public POOptimizedForEach(OperatorKey k, int rp) { |
| this(k,rp,null,null); |
| } |
| |
| public POOptimizedForEach(OperatorKey k, List inp) { |
| this(k,-1,inp,null); |
| } |
| |
| public POOptimizedForEach(OperatorKey k, int rp, List<PhysicalPlan> inp, List<Boolean> isToBeFlattened){ |
| super(k, rp); |
| setUpFlattens(isToBeFlattened); |
| this.inputPlans = inp; |
| getLeaves(); |
| } |
| |
| @Override |
| public void visit(PhyPlanVisitor v) throws VisitorException { |
| v.visitPOOptimizedForEach(this); |
| } |
| |
| @Override |
| public String name() { |
| String fString = getFlatStr(); |
| return "Optimized For Each" + "(" + fString + ")" + "[" + DataType.findTypeName(resultType) + "]" +" - " + mKey.toString(); |
| } |
| |
| /** |
| * Calls getNext on the generate operator inside the nested |
| * physical plan and returns it maintaining an additional state |
| * to denote the begin and end of the nested plan processing. |
| */ |
| @Override |
| public Result getNextTuple() throws ExecException { |
| Result res = null; |
| Result inp = null; |
| //The nested plan is under processing |
| //So return tuples that the generate oper |
| //returns |
| if(processingPlan){ |
| while(true) { |
| res = processPlan(); |
| if(res.returnStatus==POStatus.STATUS_OK) { |
| return res; |
| } |
| if(res.returnStatus==POStatus.STATUS_EOP) { |
| processingPlan = false; |
| for(PhysicalPlan plan : inputPlans) |
| plan.detachInput(); |
| return res; |
| } |
| if(res.returnStatus==POStatus.STATUS_ERR) { |
| return res; |
| } |
| if(res.returnStatus==POStatus.STATUS_NULL) { |
| continue; |
| } |
| } |
| } |
| //The nested plan processing is done or is |
| //yet to begin. So process the input and start |
| //nested plan processing on the input tuple |
| //read |
| while (true) { |
| |
| // we know that input has been attached |
| attachInputToPlans(input); |
| detachInput(); |
| res = processPlan(); |
| |
| processingPlan = true; |
| |
| return res; |
| } |
| } |
| |
| |
| /** |
| * Make a deep copy of this operator. |
| * @throws CloneNotSupportedException |
| */ |
| @Override |
| public POOptimizedForEach clone() throws CloneNotSupportedException { |
| return (POOptimizedForEach) super.clone(); |
| } |
| } |