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.master.journal.checkpoint;
  
  import java.io.IOException;
  import java.io.PrintStream;
  import javax.annotation.concurrent.NotThreadSafe;
  
  /**
   * Interface for checkpoint formats.
   *
   * Different components of Alluxio write checkpoints of their state using different formats.
   *
   * {@link CheckpointType} holds an association from checkpoint type to checkpoint format.
   */
  public interface CheckpointFormat {
    /**
     * @param in a checkpoint input stream
     * @return a reader for reading from the checkpoint
     */
    CheckpointReader createReader(CheckpointInputStream in);
  
    /**
     * @param in a checkpoint input stream
     * @param out a print stream for writing a human-readable checkpoint representation
     */
    void parseToHumanReadable(CheckpointInputStream in, PrintStream out) throws IOException;
  
    /**
     * Interface for checkpoint readers.
     */
    @NotThreadSafe
    interface CheckpointReader {}
  }
  