| /* |
| * 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.ArrayList; |
| import java.util.Collection; |
| import java.util.List; |
| |
| import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException; |
| 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.metadata.IDataSource; |
| 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.ILogicalExpressionReferenceTransform; |
| import edu.uci.ics.hyracks.algebricks.core.algebra.visitors.ILogicalOperatorVisitor; |
| |
| public class DataSourceScanOperator extends AbstractScanOperator { |
| private IDataSource<?> dataSource; |
| |
| private List<LogicalVariable> projectVars; |
| |
| private boolean projectPushed = false; |
| |
| public DataSourceScanOperator(List<LogicalVariable> variables, IDataSource<?> dataSource) { |
| super(variables); |
| this.dataSource = dataSource; |
| projectVars = new ArrayList<LogicalVariable>(); |
| } |
| |
| @Override |
| public LogicalOperatorTag getOperatorTag() { |
| return LogicalOperatorTag.DATASOURCESCAN; |
| } |
| |
| public IDataSource<?> getDataSource() { |
| return dataSource; |
| } |
| |
| @Override |
| public <R, S> R accept(ILogicalOperatorVisitor<R, S> visitor, S arg) throws AlgebricksException { |
| return visitor.visitDataScanOperator(this, arg); |
| } |
| |
| @Override |
| public boolean acceptExpressionTransform(ILogicalExpressionReferenceTransform visitor) throws AlgebricksException { |
| return false; |
| } |
| |
| @Override |
| public boolean isMap() { |
| return false; |
| } |
| |
| public void addProjectVariables(Collection<LogicalVariable> vars) { |
| projectVars.addAll(vars); |
| projectPushed = true; |
| } |
| |
| public List<LogicalVariable> getProjectVariables() { |
| return projectVars; |
| } |
| |
| public boolean isProjectPushed() { |
| return projectPushed; |
| } |
| |
| @Override |
| public VariablePropagationPolicy getVariablePropagationPolicy() { |
| return new VariablePropagationPolicy() { |
| @Override |
| public void propagateVariables(IOperatorSchema target, IOperatorSchema... sources) |
| throws AlgebricksException { |
| if (sources.length > 0) { |
| target.addAllVariables(sources[0]); |
| } |
| List<LogicalVariable> outputVariables = projectPushed ? projectVars : variables; |
| for (LogicalVariable v : outputVariables) { |
| target.addVariable(v); |
| } |
| } |
| }; |
| } |
| |
| @Override |
| public IVariableTypeEnvironment computeOutputTypeEnvironment(ITypingContext ctx) throws AlgebricksException { |
| IVariableTypeEnvironment env = createPropagatingAllInputsTypeEnvironment(ctx); |
| Object[] types = dataSource.getSchemaTypes(); |
| int i = 0; |
| for (LogicalVariable v : variables) { |
| env.setVarType(v, types[i]); |
| ++i; |
| } |
| return env; |
| } |
| } |