content: /*
   * 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.calcite.sql.validate;
  
  import org.apache.calcite.rel.type.RelDataType;
  import org.apache.calcite.sql.SqlCall;
  import org.apache.calcite.sql.SqlIdentifier;
  import org.apache.calcite.sql.SqlNode;
  
  import org.checkerframework.checker.nullness.qual.Nullable;
  
  import java.util.Map;
  
  /**
   * A scope which contains nothing besides a few parameters. Like
   * {@link EmptyScope} (which is its base class), it has no parent scope.
   *
   * @see ParameterNamespace
   */
  public class ParameterScope extends EmptyScope {
    //~ Instance fields --------------------------------------------------------
  
    /**
     * Map from the simple names of the parameters to types of the parameters
     * ({@link RelDataType}).
     */
    private final Map<String, RelDataType> nameToTypeMap;
  
    //~ Constructors -----------------------------------------------------------
  
    public ParameterScope(
        SqlValidatorImpl validator,
        Map<String, RelDataType> nameToTypeMap) {
      super(validator);
      this.nameToTypeMap = nameToTypeMap;
    }
  
    //~ Methods ----------------------------------------------------------------
  
    @Override public SqlQualified fullyQualify(SqlIdentifier identifier) {
      return SqlQualified.create(this, 1, null, identifier);
    }
  
    @Override public SqlValidatorScope getOperandScope(SqlCall call) {
      return this;
    }
  
    @Override public @Nullable RelDataType resolveColumn(String name, SqlNode ctx) {
      return nameToTypeMap.get(name);
    }
  }
  