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.noop;
  
  import alluxio.master.Master;
  import alluxio.master.StateLockManager;
  import alluxio.master.journal.CatchupFuture;
  import alluxio.master.journal.Journal;
  import alluxio.master.journal.JournalSystem;
  import alluxio.master.journal.sink.JournalSink;
  
  import java.util.Collections;
  import java.util.Map;
  import java.util.Set;
  import javax.annotation.Nullable;
  
  /**
   * Journal system which doesn't do anything.
   */
  public final class NoopJournalSystem implements JournalSystem {
    /**
     * Constructs a new {@link NoopJournalSystem}.
     */
    public NoopJournalSystem() {}
  
    @Override
    public Journal createJournal(Master master) {
      return new NoopJournal();
    }
  
    @Override
    public void gainPrimacy() {}
  
    @Override
    public void losePrimacy() {}
  
    @Override
    public void suspend(Runnable interruptCallback) {}
  
    @Override
    public void resume() {}
  
    @Override
    public CatchupFuture catchup(Map<String, Long> journalSequenceNumbers) {
      return CatchupFuture.completed();
    }
  
    @Override
    public Map<String, Long> getCurrentSequenceNumbers() {
      return Collections.emptyMap();
    }
  
    @Override
    public boolean isFormatted() {
      return true;
    }
  
    @Override
    public void addJournalSink(Master master, JournalSink journalSink) {}
  
    @Override
    public void removeJournalSink(Master master, JournalSink journalSink) {}
  
    @Override
    public Set<JournalSink> getJournalSinks(@Nullable Master master) {
      return Collections.emptySet();
    }
  
    @Override
    public boolean isEmpty() {
      return true;
    }
  
    @Override
    public void format() {}
  
    @Override
    public void start() {}
  
    @Override
    public void stop() {}
  
    @Override
    public void checkpoint(StateLockManager stateLockManager) {}
  }
  