org.apache.hadoop.hive.ql.exec.vector.expressions.IdentityExpression Maven / Gradle / Ivy
/**
* 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.hadoop.hive.ql.exec.vector.expressions;
import org.apache.hadoop.hive.ql.exec.vector.VectorExpressionDescriptor;
import org.apache.hadoop.hive.ql.exec.vector.VectorizedRowBatch;
/**
* An expression representing a column, only children are evaluated.
*/
public class IdentityExpression extends VectorExpression {
private static final long serialVersionUID = 1L;
private int colNum = -1;
private String type = null;
public IdentityExpression() {
}
public IdentityExpression(int colNum, String type) {
this.colNum = colNum;
this.type = type;
}
@Override
public void evaluate(VectorizedRowBatch batch) {
if (childExpressions != null) {
this.evaluateChildren(batch);
}
}
public static boolean isColumnOnly(VectorExpression ve) {
if (ve instanceof IdentityExpression) {
VectorExpression identityExpression = (IdentityExpression) ve;
return (identityExpression.childExpressions == null);
} else {
return false;
}
}
@Override
public int getOutputColumn() {
return colNum;
}
@Override
public String getOutputType() {
return type;
}
public int getColNum() {
return getOutputColumn();
}
public String getType() {
return getOutputType();
}
public void setColNum(int colNum) {
this.colNum = colNum;
}
public void setType(String type) {
this.type = type;
}
@Override
public VectorExpressionDescriptor.Descriptor getDescriptor() {
return (new VectorExpressionDescriptor.Builder()).build();
}
}