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* 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,
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* See the License for the specific language governing permissions and
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package org.apache.drill.exec.planner.physical.visitor;
import java.util.ArrayList;
import java.util.List;
import org.apache.calcite.rel.type.RelDataTypeFactory;
import org.apache.calcite.rex.RexBuilder;
import org.apache.calcite.rex.RexCall;
import org.apache.calcite.rex.RexCorrelVariable;
import org.apache.calcite.rex.RexDynamicParam;
import org.apache.calcite.rex.RexFieldAccess;
import org.apache.calcite.rex.RexInputRef;
import org.apache.calcite.rex.RexLiteral;
import org.apache.calcite.rex.RexLocalRef;
import org.apache.calcite.rex.RexNode;
import org.apache.calcite.rex.RexOver;
import org.apache.calcite.rex.RexRangeRef;
import org.apache.calcite.rex.RexVisitorImpl;
import org.apache.drill.exec.expr.fn.FunctionImplementationRegistry;
import org.apache.drill.exec.planner.physical.ProjectPrel;
import org.apache.drill.exec.planner.types.RelDataTypeDrillImpl;
import org.apache.drill.exec.planner.types.RelDataTypeHolder;
public class RexVisitorComplexExprSplitter extends RexVisitorImpl<RexNode> {
RelDataTypeFactory factory;
FunctionImplementationRegistry funcReg;
List<RexNode> complexExprs;
List<ProjectPrel> projects;
int lastUsedIndex;
public RexVisitorComplexExprSplitter(RelDataTypeFactory factory, FunctionImplementationRegistry funcReg, int firstUnused) {
super(true);
this.factory = factory;
this.funcReg = funcReg;
this.complexExprs = new ArrayList<>();
this.lastUsedIndex = firstUnused;
}
public List<RexNode> getComplexExprs() {
return complexExprs;
}
@Override
public RexNode visitInputRef(RexInputRef inputRef) {
return inputRef;
}
@Override
public RexNode visitLocalRef(RexLocalRef localRef) {
return localRef;
}
@Override
public RexNode visitLiteral(RexLiteral literal) {
return literal;
}
@Override
public RexNode visitOver(RexOver over) {
return over;
}
@Override
public RexNode visitCorrelVariable(RexCorrelVariable correlVariable) {
return correlVariable;
}
@Override
public RexNode visitCall(RexCall call) {
String functionName = call.getOperator().getName();
List<RexNode> newOps = new ArrayList<>();
for (RexNode operand : call.operands) {
newOps.add(operand.accept(this));
}
if (funcReg.isFunctionComplexOutput(functionName) ) {
RexBuilder builder = new RexBuilder(factory);
RexNode ret = builder.makeInputRef( new RelDataTypeDrillImpl(new RelDataTypeHolder(), factory), lastUsedIndex);
lastUsedIndex++;
complexExprs.add(call.clone(new RelDataTypeDrillImpl(new RelDataTypeHolder(),factory), newOps));
return ret;
}
return call.clone(call.getType(), newOps);
}
@Override
public RexNode visitDynamicParam(RexDynamicParam dynamicParam) {
return dynamicParam;
}
@Override
public RexNode visitRangeRef(RexRangeRef rangeRef) {
return rangeRef;
}
@Override
public RexNode visitFieldAccess(RexFieldAccess fieldAccess) {
return fieldAccess;
}
}