content: /*
   * Copyright 1999-2018 Alibaba Group Holding Ltd.
   *
   * 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.
   */
  
  package com.alibaba.nacos.config.server.service.dump.disk;
  
  /**
   * config disk serve factory.
   *
   * @author zunfei.lzf
   */
  public class ConfigDiskServiceFactory {
      
      static ConfigDiskService configDiskService;
      
      private static final String TYPE_RAW_DISK = "rawdisk";
      
      private static final String TYPE_ROCKSDB = "rocksdb";
      
      /**
       * get disk service.
       *
       * @return
       */
      public static ConfigDiskService getInstance() {
          if (configDiskService == null) {
              synchronized (ConfigDiskServiceFactory.class) {
                  if (configDiskService == null) {
                      String type = System.getProperty("config_disk_type", TYPE_RAW_DISK);
                      if (type.equalsIgnoreCase(TYPE_ROCKSDB)) {
                          configDiskService = new ConfigRocksDbDiskService();
                      } else {
                          configDiskService = new ConfigRawDiskService();
                      }
                  }
                  return configDiskService;
              }
          }
          return configDiskService;
      }
      
  }
  