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;
  
  import alluxio.proto.journal.Journal;
  
  import java.util.List;
  
  /**
   * The interface for a journal entry merge which merges multiple inode journals on the
   * same inode object into one.
   */
  public interface JournalEntryMerger {
    /**
     * Adds a new journal entry.
     * @param entry the new journal entry to add
     */
    void add(Journal.JournalEntry entry);
  
    /**
     * Returns a list of journal entries which have been merged.
     * @return the merged journal entries
     */
    List<Journal.JournalEntry> getMergedJournalEntries();
  
    /**
     * Clears the existing journal entries.
     */
    void clear();
  }
  