| /* |
| * 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.drill.exec.expr; |
| |
| import com.google.common.collect.ImmutableSet; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| import org.apache.drill.common.expression.ExpressionPosition; |
| import org.apache.drill.common.expression.LogicalExpression; |
| import org.apache.drill.common.expression.PathSegment; |
| import org.apache.drill.common.expression.visitors.ExprVisitor; |
| import org.apache.drill.common.types.TypeProtos.MajorType; |
| import org.apache.drill.exec.record.TypedFieldId; |
| |
| import java.util.Iterator; |
| |
| /** |
| * Wraps a value vector field to be read, providing metadata about the field. |
| * Also may contain batch naming information to which this field belongs. If |
| * such information is absent default naming will be used from mapping set |
| * during materialization. |
| */ |
| public class ValueVectorReadExpression implements LogicalExpression { |
| static final Logger logger = LoggerFactory.getLogger(ValueVectorReadExpression.class); |
| |
| private final TypedFieldId fieldId; |
| private final BatchReference batchRef; |
| |
| public ValueVectorReadExpression(TypedFieldId tfId){ |
| this(tfId, null); |
| } |
| |
| public ValueVectorReadExpression(TypedFieldId tfId, BatchReference batchRef){ |
| this.fieldId = tfId; |
| this.batchRef = batchRef; |
| } |
| |
| public BatchReference getBatchRef() { |
| return batchRef; |
| } |
| |
| public boolean hasReadPath(){ |
| return fieldId.hasRemainder(); |
| } |
| |
| public PathSegment getReadPath(){ |
| return fieldId.getRemainder(); |
| } |
| |
| public TypedFieldId getTypedFieldId(){ |
| return fieldId; |
| } |
| |
| public boolean isSuperReader(){ |
| return fieldId.isHyperReader(); |
| } |
| @Override |
| public MajorType getMajorType() { |
| return fieldId.getFinalType(); |
| } |
| |
| @Override |
| public <T, V, E extends Exception> T accept(ExprVisitor<T, V, E> visitor, V value) throws E { |
| if (visitor instanceof AbstractExecExprVisitor) { |
| AbstractExecExprVisitor<T, V, E> abstractExecExprVisitor = (AbstractExecExprVisitor<T, V, E>) visitor; |
| return abstractExecExprVisitor.visitValueVectorReadExpression(this, value); |
| } |
| return visitor.visitUnknown(this, value); |
| } |
| |
| public TypedFieldId getFieldId() { |
| return fieldId; |
| } |
| |
| @Override |
| public ExpressionPosition getPosition() { |
| return ExpressionPosition.UNKNOWN; |
| } |
| |
| @Override |
| public Iterator<LogicalExpression> iterator() { |
| return ImmutableSet.<LogicalExpression>of().iterator(); |
| } |
| |
| @Override |
| public int getSelfCost() { |
| return 0; // TODO |
| } |
| |
| @Override |
| public int getCumulativeCost() { |
| return 0; // TODO |
| } |
| |
| @Override |
| public String toString() { |
| return "ValueVectorReadExpression [fieldId=" + fieldId + "]"; |
| } |
| } |