/**
* 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.hadoop.hive.ql.optimizer.lineage;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.Map;
import org.apache.hadoop.hive.ql.lib.DefaultRuleDispatcher;
import org.apache.hadoop.hive.ql.lib.Dispatcher;
import org.apache.hadoop.hive.ql.lib.GraphWalker;
import org.apache.hadoop.hive.ql.lib.Node;
import org.apache.hadoop.hive.ql.lib.NodeProcessor;
import org.apache.hadoop.hive.ql.lib.PreOrderWalker;
import org.apache.hadoop.hive.ql.lib.Rule;
import org.apache.hadoop.hive.ql.lib.RuleRegExp;
import org.apache.hadoop.hive.ql.optimizer.Transform;
import org.apache.hadoop.hive.ql.parse.ParseContext;
import org.apache.hadoop.hive.ql.parse.SemanticException;
import org.apache.hadoop.hive.ql.session.SessionState;
/**
* This class generates the lineage information for the columns
* and tables from the plan before it goes through other
* optimization phases.
*/
public class Generator implements Transform {
/* (non-Javadoc)
* @see org.apache.hadoop.hive.ql.optimizer.Transform#transform(org.apache.hadoop.hive.ql.parse.ParseContext)
*/
@Override
public ParseContext transform(ParseContext pctx) throws SemanticException {
// Create the lineage context
LineageCtx lCtx = new LineageCtx(pctx);
Map<Rule, NodeProcessor> opRules = new LinkedHashMap<Rule, NodeProcessor>();
opRules.put(new RuleRegExp("R1", "TS%"), OpProcFactory.getTSProc());
opRules.put(new RuleRegExp("R2", "SCR%"), OpProcFactory.getTransformProc());
opRules.put(new RuleRegExp("R3", "UDTF%"), OpProcFactory.getTransformProc());
opRules.put(new RuleRegExp("R4", "SEL%"), OpProcFactory.getSelProc());
opRules.put(new RuleRegExp("R5", "GBY%"), OpProcFactory.getGroupByProc());
opRules.put(new RuleRegExp("R6", "UNION%"), OpProcFactory.getUnionProc());
opRules.put(new RuleRegExp("R7", "JOIN%|MAPJOIN%"), OpProcFactory.getJoinProc());
opRules.put(new RuleRegExp("R8", "RS%"), OpProcFactory.getReduceSinkProc());
opRules.put(new RuleRegExp("R9", "LVJ%"), OpProcFactory.getLateralViewJoinProc());
// The dispatcher fires the processor corresponding to the closest matching rule and passes the context along
Dispatcher disp = new DefaultRuleDispatcher(OpProcFactory.getDefaultProc(), opRules, lCtx);
GraphWalker ogw = new PreOrderWalker(disp);
// Create a list of topop nodes
ArrayList<Node> topNodes = new ArrayList<Node>();
topNodes.addAll(pctx.getTopOps().values());
ogw.startWalking(topNodes, null);
// Transfer the index from the lineage context to the session state.
if (SessionState.get() != null) {
SessionState.get().getLineageState().setIndex(lCtx.getIndex());
}
return pctx;
}
}