| /* |
| * 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.newplan.logical.relational; |
| |
| import java.util.List; |
| |
| import org.apache.pig.SortColInfo; |
| import org.apache.pig.SortColInfo.Order; |
| import org.apache.pig.backend.hadoop.executionengine.physicalLayer.LogicalToPhysicalTranslatorException; |
| import org.apache.pig.impl.logicalLayer.FrontendException; |
| import org.apache.pig.newplan.Operator; |
| import org.apache.pig.newplan.OperatorPlan; |
| import org.apache.pig.newplan.logical.visitor.UDFFinder; |
| |
| public class MapSideMergeValidator { |
| |
| public boolean validateMapSideMerge(List<Operator> preds, OperatorPlan lp) |
| throws LogicalToPhysicalTranslatorException{ |
| int errCode = 1103; |
| String errMsg = "Merge join/Cogroup only supports Filter, Foreach, " + |
| "Ascending Sort, or Load as its predecessors. Found : "; |
| if (preds != null) { |
| for(Operator lo : preds) { |
| if (!(lo instanceof LOFilter |
| || lo instanceof LOGenerate || lo instanceof LOInnerLoad |
| || lo instanceof LOLoad || lo instanceof LOSplitOutput |
| || lo instanceof LOSplit |
| || isAcceptableSortOp(lo) |
| || isAcceptableForEachOp(lo))) { |
| throw new LogicalToPhysicalTranslatorException(errMsg, errCode); |
| } |
| |
| // Repeat until LOSort or top of the tree is reached. |
| if (! (lo instanceof LOSort)) { |
| validateMapSideMerge(lp.getPredecessors(lo),lp); |
| } |
| } |
| } |
| // We visited everything and all is good. |
| return true; |
| } |
| |
| private boolean isAcceptableForEachOp(Operator lo) throws LogicalToPhysicalTranslatorException { |
| if (lo instanceof LOForEach) { |
| OperatorPlan innerPlan = ((LOForEach) lo).getInnerPlan(); |
| validateMapSideMerge(innerPlan.getSinks(), innerPlan); |
| return !containsUDFs((LOForEach) lo); |
| } else { |
| return false; |
| } |
| } |
| |
| private boolean isAcceptableSortOp(Operator op) throws LogicalToPhysicalTranslatorException { |
| if (!(op instanceof LOSort)) { |
| return false; |
| } |
| LOSort sort = (LOSort) op; |
| try { |
| for (SortColInfo colInfo : sort.getSortInfo().getSortColInfoList()) { |
| // TODO: really, we should check that the sort is on the join keys, in the same order! |
| if (colInfo.getSortOrder() != Order.ASCENDING) { |
| return false; |
| } |
| } |
| } catch (FrontendException e) { |
| throw new LogicalToPhysicalTranslatorException(e); |
| } |
| return true; |
| } |
| |
| private boolean containsUDFs(LOForEach fo) throws LogicalToPhysicalTranslatorException { |
| LogicalPlan logExpPlan = fo.getInnerPlan(); |
| UDFFinder udfFinder; |
| try { |
| udfFinder = new UDFFinder(logExpPlan); |
| udfFinder.visit(); |
| // TODO (dvryaboy): in the future we could relax this rule by tracing what fields |
| // are being passed into the UDF, and only refusing if the UDF is working on the |
| // join key. Transforms of other fields should be ok. |
| if (udfFinder.getUDFList().size() != 0) { |
| return true; |
| } |
| } catch (FrontendException e) { |
| throw new LogicalToPhysicalTranslatorException(e); |
| } |
| return false; |
| } |
| } |