| /** |
| * Copyright 2011-2015 Quickstep Technologies LLC. |
| * Copyright 2015 Pivotal Software, Inc. |
| * |
| * Licensed 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_TYPES_TYPE_FACTORY_HPP_ |
| #define QUICKSTEP_TYPES_TYPE_FACTORY_HPP_ |
| |
| #include <cstddef> |
| |
| #include "types/TypeID.hpp" |
| #include "utility/Macros.hpp" |
| |
| namespace quickstep { |
| |
| class Type; |
| |
| namespace serialization { class Type; } |
| |
| /** \addtogroup Types |
| * @{ |
| */ |
| |
| /** |
| * @brief All-static factory object that provides access to Types, as well as |
| * methods for determining coercibility of Types. |
| **/ |
| class TypeFactory { |
| public: |
| /** |
| * @brief Determine if a length parameter is required when getting a Type of |
| * the specified TypeID. |
| * |
| * @param id The id of the desired Type. |
| * @return Whether a length must be specified for Types of the given id. |
| **/ |
| static bool TypeRequiresLengthParameter(const TypeID id) { |
| switch (id) { |
| case kInt: |
| case kLong: |
| case kFloat: |
| case kDouble: |
| case kDatetime: |
| case kDatetimeInterval: |
| case kYearMonthInterval: |
| case kNullType: |
| return false; |
| case kChar: |
| case kVarChar: |
| return true; |
| default: |
| FATAL_ERROR("Unrecognized TypeID in TypeFactory::TypeRequiresLengthParameter"); |
| } |
| } |
| |
| /** |
| * @brief Factory method to get a Type by its TypeID. |
| * @note This version is for Types without a length parameter (currently |
| * IntType, LongType, FloatType, and DoubleType). It is an error to |
| * call this with a Type which requires a length parameter. |
| * |
| * @param id The id of the desired Type. |
| * @param nullable Whether to get the nullable version of the Type. |
| * @return The Type corresponding to id. |
| **/ |
| static const Type& GetType(const TypeID id, const bool nullable = false); |
| |
| /** |
| * @brief Factory method to get a Type by its TypeID and length. |
| * @note This version is for Types with a length parameter (currently |
| * CharType and VarCharType). It is an error to call this with a Type |
| * which does not require a length parameter. |
| * |
| * @param id The id of the desired Type. |
| * @param length The length parameter of the desired Type. |
| * @param nullable Whether to get the nullable version of the Type. |
| * @return The Type corresponding to id and length. |
| **/ |
| static const Type& GetType(const TypeID id, const std::size_t length, const bool nullable = false); |
| |
| /** |
| * @brief Get a reference to a Type from that Type's serialized Protocol Buffer |
| * representation. |
| * |
| * @param proto A serialized Protocol Buffer representation of a Type, |
| * originally generated by getProto(). |
| * @return The Type described by proto. |
| **/ |
| static const Type& ReconstructFromProto(const serialization::Type &proto); |
| |
| /** |
| * @brief Check whether a serialization::Type is fully-formed and |
| * all parts are valid. |
| * |
| * @param proto A serialized Protocol Buffer representation of a Type, |
| * originally generated by getProto(). |
| * @return Whether proto is fully-formed and valid. |
| **/ |
| static bool ProtoIsValid(const serialization::Type &proto); |
| |
| /** |
| * @brief Determine which of two types is most specific, i.e. which |
| * isSafelyCoercibleFrom() the other. |
| * |
| * @param first The first type to check. |
| * @param second The second type to check. |
| * @return The most precise type, or NULL if neither Type |
| * isSafelyCoercibleFrom() the other. |
| **/ |
| static const Type* GetMostSpecificType(const Type &first, const Type &second); |
| |
| /** |
| * @brief Determine a type, if any exists, which both arguments can be safely |
| * coerced to. It is possible that the resulting type may not be |
| * either argument. |
| * |
| * @param first The first type to check. |
| * @param second The second type to check. |
| * @return The unifying type, or NULL if none exists. |
| **/ |
| static const Type* GetUnifyingType(const Type &first, const Type &second); |
| |
| private: |
| // Undefined default constructor. Class is all-static and should not be |
| // instantiated. |
| TypeFactory(); |
| |
| DISALLOW_COPY_AND_ASSIGN(TypeFactory); |
| }; |
| |
| /** @} */ |
| |
| } // namespace quickstep |
| |
| #endif // QUICKSTEP_TYPES_TYPE_FACTORY_HPP_ |