content: /*
   * Copyright (C) 2010-2101 Alibaba Group Holding Limited.
   *
   * 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.otter.node.etl.common.io.download;
  
  import org.apache.commons.lang.StringUtils;
  import org.apache.commons.lang.SystemUtils;
  
  import com.alibaba.otter.node.etl.common.io.download.exception.DataRetrieveException;
  import com.alibaba.otter.node.etl.common.io.download.impl.aria2c.Aria2cRetriever;
  import com.alibaba.otter.shared.common.model.config.parameter.SystemParameter.RetrieverType;
  
  /**
   * DataRetriever工厂，选择合适的下载器
   * 
   * @author jianghang 2011-11-3 下午07:42:05
   * @version 4.0.0
   */
  public class DataRetrieverFactory {
  
      public DataRetriever createRetriever(RetrieverType type, String url, String targetDir) {
          if (type.isAria2c()) {
              return getAria2cRetriever(type.getExe(), url, targetDir);
          } else {
              // 其他的类型
          }
  
          throw new DataRetrieveException("no DataRetriever for[" + type + "]");
      }
  
      private DataRetriever getAria2cRetriever(String cmd, String url, String targetDir) {
          if (StringUtils.isEmpty(cmd)) {
              cmd = (SystemUtils.IS_OS_WINDOWS ? cmd + ".exe" : cmd);
          }
          return new Aria2cRetriever(cmd, url, targetDir);
      }
  }
  