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.journalv0;
  
  import alluxio.master.journalv0.ufs.UfsMutableJournal;
  import alluxio.util.URIUtils;
  
  import java.io.IOException;
  import java.net.URI;
  import java.net.URISyntaxException;
  import javax.annotation.concurrent.ThreadSafe;
  
  /**
   * The read-write journal. This allows both reads and writes to the journal.
   */
  @ThreadSafe
  public interface MutableJournal extends Journal {
  
    /**
     * A {@link MutableJournal} factory.
     */
    @ThreadSafe
    final class Factory implements JournalFactory {
      private final URI mBase;
  
      /**
       * Creates a read-write journal factory with the specified base location. When journals are
       * created, their names are appended to the base path.
       *
       * @param base the base location for journals created by this factory
       */
      public Factory(URI base) {
        mBase = base;
      }
  
      @Override
      public MutableJournal create(String name) {
        try {
          return new UfsMutableJournal(URIUtils.appendPath(mBase, name));
        } catch (URISyntaxException e) {
          throw new RuntimeException(e);
        }
      }
  
      /**
       * Creates a new read-write journal using the given location.
       *
       * @param location the journal location
       * @return a new instance of {@link Journal}
       */
      public static MutableJournal create(URI location) {
        return new UfsMutableJournal(location);
      }
    }
  
    /**
     * Formats the journal.
     */
    void format() throws IOException;
  
    /**
     * @return the {@link JournalWriter} for this journal
     */
    JournalWriter getWriter();
  }
  