expressions/ExpressionFactories.hpp

/**
 * 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.
 **/

#ifndef QUICKSTEP_EXPRESSIONS_EXPRESSION_FACTORIES_HPP_
#define QUICKSTEP_EXPRESSIONS_EXPRESSION_FACTORIES_HPP_

#include "utility/Macros.hpp"

namespace quickstep {

class CatalogDatabaseLite;
class Predicate;
class Scalar;

namespace serialization {
class Predicate;
class Scalar;
}  // namespace serialization

/** \addtogroup Expressions
 *  @{
 */

/**
 * @brief All-static factory object that provides access to Predicates.
 **/
class PredicateFactory {
 public:
  /**
   * @brief Get a pointer to a Predicate from its serialized Protocol Buffer
   *        form.
   *
   * @param proto The Protocol Buffer representation of a Predicate object,
   *        originally generated by getProto().
   * @param database The Database to resolve relation and attribute references
   *        in.
   * @return A new Predicate reconstructed from the supplied Protocol Buffer.
   **/
  static Predicate* ReconstructFromProto(const serialization::Predicate &proto,
                                         const CatalogDatabaseLite &database);

  /**
   * @brief Check whether a serialization::Predicate is fully-formed and
   *        all parts are valid.
   *
   * @param proto A serialized Protocol Buffer representation of a Predicate,
   *        originally generated by getProto().
   * @param database The Database to resolve relation and attribute references
   *        in.
   * @return Whether proto is fully-formed and valid.
   **/
  static bool ProtoIsValid(const serialization::Predicate &proto,
                           const CatalogDatabaseLite &database);

 private:
  // Undefined default constructor. Class is all-static and should not be
  // instantiated.
  PredicateFactory();

  DISALLOW_COPY_AND_ASSIGN(PredicateFactory);
};

/**
 * @brief All-static factory object that provides access to Scalars.
 **/
class ScalarFactory {
 public:
  /**
   * @brief Get a pointer to a Scalar from its serialized Protocol Buffer form.
   *
   * @param proto The Protocol Buffer representation of a Scalar object,
   *        originally generated by getProto().
   * @param database The Database to resolve relation and attribute references
   *        in.
   * @return A new Scalar reconstructed from the supplied Protocol Buffer.
   **/
  static Scalar* ReconstructFromProto(const serialization::Scalar &proto,
                                      const CatalogDatabaseLite &database);

  /**
   * @brief Check whether a serialization::Scalar is fully-formed and
   *        all parts are valid.
   *
   * @param proto A serialized Protocol Buffer representation of a Scalar,
   *        originally generated by getProto().
   * @param database The Database to resolve relation and attribute references
   *        in.
   * @return Whether proto is fully-formed and valid.
   **/
  static bool ProtoIsValid(const serialization::Scalar &proto,
                           const CatalogDatabaseLite &database);

 private:
  // Undefined default constructor. Class is all-static and should not be
  // instantiated.
  ScalarFactory();

  DISALLOW_COPY_AND_ASSIGN(ScalarFactory);
};

/** @} */

}  // namespace quickstep

#endif  // QUICKSTEP_EXPRESSIONS_EXPRESSION_FACTORIES_HPP_