| /* |
| * Copyright 2009-2010 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.List; |
| |
| 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.LogicalOperatorTag; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalVariable; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.expressions.IVariableTypeEnvironment; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.properties.VariablePropagationPolicy; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.typing.ITypingContext; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.visitors.ILogicalOperatorVisitor; |
| |
| /** |
| * It corresponds to the Map operator in other algebras. |
| * |
| * @author Nicola |
| */ |
| |
| public class AssignOperator extends AbstractAssignOperator { |
| |
| public AssignOperator(List<LogicalVariable> vars, List<Mutable<ILogicalExpression>> exprs) { |
| super(vars, exprs); |
| } |
| |
| public AssignOperator(LogicalVariable var, Mutable<ILogicalExpression> expr) { |
| super(); |
| this.variables.add(var); |
| this.expressions.add(expr); |
| } |
| |
| @Override |
| public LogicalOperatorTag getOperatorTag() { |
| return LogicalOperatorTag.ASSIGN; |
| } |
| |
| @Override |
| public <R, T> R accept(ILogicalOperatorVisitor<R, T> visitor, T arg) throws AlgebricksException { |
| return visitor.visitAssignOperator(this, arg); |
| } |
| |
| @Override |
| public VariablePropagationPolicy getVariablePropagationPolicy() { |
| return new VariablePropagationPolicy() { |
| |
| @Override |
| public void propagateVariables(IOperatorSchema target, IOperatorSchema... sources) |
| throws AlgebricksException { |
| target.addAllVariables(sources[0]); |
| for (LogicalVariable v : variables) { |
| target.addVariable(v); |
| } |
| } |
| }; |
| |
| } |
| |
| @Override |
| public boolean isMap() { |
| return true; |
| } |
| |
| @Override |
| public IVariableTypeEnvironment computeOutputTypeEnvironment(ITypingContext ctx) throws AlgebricksException { |
| IVariableTypeEnvironment env = createPropagatingAllInputsTypeEnvironment(ctx); |
| int n = variables.size(); |
| for (int i = 0; i < n; i++) { |
| env.setVarType( |
| variables.get(i), |
| ctx.getExpressionTypeComputer().getType(expressions.get(i).getValue(), ctx.getMetadataProvider(), |
| env)); |
| } |
| return env; |
| } |
| |
| @Override |
| public boolean requiresVariableReferenceExpressions() { |
| return false; |
| } |
| } |