| /* |
| * Copyright 2009-2013 by The Regents of the University of California |
| * Licensed 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 from |
| * |
| * 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 edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical; |
| |
| import java.util.ArrayList; |
| |
| import org.apache.commons.lang3.mutable.Mutable; |
| |
| import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalExpression; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalExpressionTag; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalOperatorTag; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalVariable; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.expressions.AbstractFunctionCallExpression; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.expressions.IVariableTypeEnvironment; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.expressions.VariableReferenceExpression; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.functions.AlgebricksBuiltinFunctions; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.properties.TypePropagationPolicy; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.properties.VariablePropagationPolicy; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.typing.ITypeEnvPointer; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.typing.ITypingContext; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.typing.OpRefTypeEnvPointer; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.typing.PropagatingTypeEnvironment; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.visitors.ILogicalExpressionReferenceTransform; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.visitors.ILogicalOperatorVisitor; |
| |
| public class SelectOperator extends AbstractLogicalOperator { |
| private final Mutable<ILogicalExpression> condition; |
| |
| public SelectOperator(Mutable<ILogicalExpression> condition) { |
| this.condition = condition; |
| } |
| |
| @Override |
| public LogicalOperatorTag getOperatorTag() { |
| return LogicalOperatorTag.SELECT; |
| } |
| |
| public Mutable<ILogicalExpression> getCondition() { |
| return condition; |
| } |
| |
| @Override |
| public void recomputeSchema() { |
| schema = new ArrayList<LogicalVariable>(inputs.get(0).getValue().getSchema()); |
| } |
| |
| @Override |
| public VariablePropagationPolicy getVariablePropagationPolicy() { |
| return VariablePropagationPolicy.ALL; |
| } |
| |
| @Override |
| public boolean acceptExpressionTransform(ILogicalExpressionReferenceTransform visitor) throws AlgebricksException { |
| return visitor.transform(condition); |
| } |
| |
| @Override |
| public <R, T> R accept(ILogicalOperatorVisitor<R, T> visitor, T arg) throws AlgebricksException { |
| return visitor.visitSelectOperator(this, arg); |
| } |
| |
| @Override |
| public boolean isMap() { |
| return true; |
| } |
| |
| @Override |
| public IVariableTypeEnvironment computeOutputTypeEnvironment(ITypingContext ctx) throws AlgebricksException { |
| ITypeEnvPointer[] envPointers = new ITypeEnvPointer[1]; |
| envPointers[0] = new OpRefTypeEnvPointer(inputs.get(0), ctx); |
| PropagatingTypeEnvironment env = new PropagatingTypeEnvironment(ctx.getExpressionTypeComputer(), |
| ctx.getNullableTypeComputer(), ctx.getMetadataProvider(), TypePropagationPolicy.ALL, envPointers); |
| if (condition.getValue().getExpressionTag() == LogicalExpressionTag.FUNCTION_CALL) { |
| AbstractFunctionCallExpression f1 = (AbstractFunctionCallExpression) condition.getValue(); |
| if (f1.getFunctionIdentifier().equals(AlgebricksBuiltinFunctions.NOT)) { |
| ILogicalExpression a1 = f1.getArguments().get(0).getValue(); |
| if (a1.getExpressionTag() == LogicalExpressionTag.FUNCTION_CALL) { |
| AbstractFunctionCallExpression f2 = (AbstractFunctionCallExpression) a1; |
| if (f2.getFunctionIdentifier().equals(AlgebricksBuiltinFunctions.IS_NULL)) { |
| ILogicalExpression a2 = f2.getArguments().get(0).getValue(); |
| if (a2.getExpressionTag() == LogicalExpressionTag.VARIABLE) { |
| LogicalVariable var = ((VariableReferenceExpression) a2).getVariableReference(); |
| env.getNonNullVariables().add(var); |
| } |
| } |
| } |
| } |
| } |
| return env; |
| } |
| |
| @Override |
| public boolean requiresVariableReferenceExpressions() { |
| return false; |
| } |
| } |