text: // Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
  //
  // 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.
  
  #pragma once
  
  #include <string>
  #include <vector>
  
  #include "cube/error.h"
  
  namespace rec {
  namespace mcube {
  
  class VirtualDict {
   public:
    VirtualDict() {}
  
    virtual ~VirtualDict() {}
  
    virtual int load(const std::string& /*dict_path*/,
                     bool /*in_mem*/,
                     const std::string& /*v_path*/) {
      return E_NOT_IMPL;
    }
  
    virtual int load(const std::vector<std::string>& /*dict_path*/,
                     bool /*in_mem*/,
                     const std::string& /*v_path*/) {
      return E_NOT_IMPL;
    }
  
    virtual int destroy() { return E_NOT_IMPL; }
  
    virtual const std::string& version() {
      static std::string UNKNOWN_VERSION = "UNKNOWN";
      return UNKNOWN_VERSION;
    }
  
    virtual std::string guard_version() {
      static std::string UNKNOWN_VERSION = "UNKNOWN";
      return UNKNOWN_VERSION;
    }
  
    virtual void set_base_dict(const VirtualDict* dict) = 0;
  
    virtual bool seek(uint64_t key, char* buff, uint64_t* buff_size) = 0;
  
    virtual void atom_inc_seek_num() = 0;
  
    virtual void atom_dec_seek_num() = 0;
    virtual uint32_t atom_seek_num() = 0;
  };  // class VirtualDict
  
  }  // namespace mcube
  }  // namespace rec
  