content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  package org.apache.asterix.common.transactions;
  
  import org.apache.hyracks.api.exceptions.HyracksDataException;
  import org.apache.hyracks.api.lifecycle.ILifeCycleComponent;
  
  public interface ICheckpointManager extends ILifeCycleComponent {
  
      /**
       * @return The latest checkpoint on disk if any exists. Otherwise null.
       */
      Checkpoint getLatest();
  
      /**
       * Performs a sharp checkpoint.
       *
       * @throws HyracksDataException
       */
      void doSharpCheckpoint() throws HyracksDataException;
  
      /**
       * Attempts to perform a soft checkpoint at the specified {@code checkpointTargetLSN}.
       *
       * @param checkpointTargetLSN
       * @return The LSN recorded on the captured checkpoint.
       * @throws HyracksDataException
       */
      long tryCheckpoint(long checkpointTargetLSN) throws HyracksDataException;
  
      /**
       * Secures the current low-water mark until the transaction identified by {@code id} completes.
       *
       * @param id
       * @throws HyracksDataException
       */
      void secure(TxnId id) throws HyracksDataException;
  
      /**
       * Notifies this {@link ICheckpointManager} that the transaction identified by {@code id} completed.
       *
       * @param id
       */
      void completed(TxnId id);
  
      /**
       * Checkpoints idle datasets by flushing their in-memory component to disk if needed.
       *
       * @throws HyracksDataException
       */
      void checkpointIdleDatasets() throws HyracksDataException;
  
      /**
       * Suspends checkpointing datasets
       */
      void suspend();
  
      /**
       * Resumes checkpointing datasets
       */
      void resume();
  }
  