/**
 * 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.plan;

import java.util.ArrayList;
import java.util.List;

import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.hive.serde2.typeinfo.TypeInfo;

/**
 * Dummy desc only for populating TOK_ALLCOLREF and should not be used
 * outside of TypeCheckProcFactory
 */
public class ExprNodeColumnListDesc extends ExprNodeDesc {

  // column or constant
  final List<ExprNodeDesc> columns = new ArrayList<ExprNodeDesc>();

  public void addColumn(ExprNodeDesc column) {
    columns.add(column);
  }

  @Override
  public ExprNodeDesc clone() {
    ExprNodeColumnListDesc clone = new ExprNodeColumnListDesc();
    clone.columns.addAll(columns);
    return clone;
  }

  @Override
  public boolean isSame(Object o) {
    if (o instanceof ExprNodeColumnListDesc) {
      return columns.equals(((ExprNodeColumnListDesc)o).columns);
    }
    return false;
  }

  @Override
  public TypeInfo getTypeInfo() {
    throw new IllegalStateException();
  }

  @Override
  public void setTypeInfo(TypeInfo typeInfo) {
    throw new IllegalStateException();
  }

  @Override
  public ObjectInspector getWritableObjectInspector() {
    throw new IllegalStateException();
  }

  @Override
  public String getTypeString() {
    throw new IllegalStateException();
  }

  @Override
  public List<String> getCols() {
    throw new IllegalStateException();
  }

  @Override
  public List<ExprNodeDesc> getChildren() {
    return new ArrayList<ExprNodeDesc>(columns);
  }
}