content: /*
   * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
   * (the "License"). You may not use this work except in compliance with the License, which is
   * available at www.apache.org/licenses/LICENSE-2.0
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied, as more fully set forth in the License.
   *
   * See the NOTICE file distributed with this work for information regarding copyright ownership.
   */
  
  package alluxio.util.compression;
  
  import alluxio.conf.Configuration;
  import alluxio.conf.PropertyKey;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.nio.file.Path;
  
  /**
   * Interface for a directory marshaller to follow.
   */
  public interface DirectoryMarshaller {
    /**
     * Writes the contents of path ot outputStream such that it can be read by
     * {@link #read(Path, InputStream)}.
     * @param path the directory to marshall
     * @param outputStream the output stream that the marshalled information
     * @return the number of bytes read in path
     */
    long write(Path path, OutputStream outputStream) throws IOException, InterruptedException;
  
    /**
     * Reads the content from the inputStream and writes them to the specified path.
     * @param path the output path
     * @param inputStream the stream to read the data from
     * @return the number of bytes written to path
     */
    long read(Path path, InputStream inputStream) throws IOException;
  
    /**
     * An enum to represent the different {@link DirectoryMarshaller} types.
     */
    enum Type {
      NO_COMPRESSION,
      GZIP,
      TAR_GZIP,
    }
  
    /**
     * Factory to access the DirectoryMarshaller.
     */
    class Factory {
      /**
       * @return a {@link DirectoryMarshaller}
       */
      public static DirectoryMarshaller create() {
        Type compressionType = Configuration.getEnum(
            PropertyKey.MASTER_EMBEDDED_JOURNAL_SNAPSHOT_REPLICATION_COMPRESSION_TYPE, Type.class);
        switch (compressionType) {
          case GZIP:
            return new GzipMarshaller();
          case TAR_GZIP:
            return new TarGzMarshaller();
          default:
            return new NoCompressionMarshaller();
        }
      }
    }
  }
  