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;
  
  import java.util.Collections;
  import java.util.Map;
  import java.util.Set;
  
  /**
   * This class is used to represent what the active syncing process should sync.
   */
  public class SyncInfo {
    public static final long INVALID_TXID = -1;
    private static final SyncInfo EMPTY_INFO = new SyncInfo(Collections.emptyMap(),
        false, INVALID_TXID);
  
    // A map mapping syncpoints to files changed in those sync points
    private final Map<AlluxioURI, Set<AlluxioURI>> mChangedFilesMap;
  
    // Ignore the changed files and simply sync the entire directory
    private final boolean mForceSync;
  
    // transaction id that we can restart from once this sync is complete
    private final long mTxId;
  
    /**
     * Constructs a SyncInfo.
     *
     * @param changedFiles a map mapping syncpoint to changed files
     * @param forceSync force sync the entire directory
     * @param txId the transaction id  that is synced in this sync
     */
    public SyncInfo(Map<AlluxioURI, Set<AlluxioURI>> changedFiles, boolean forceSync, long txId) {
      mChangedFilesMap = changedFiles;
      mForceSync = forceSync;
      mTxId = txId;
    }
  
    /**
     * Returns an empty SyncInfo object.
     *
     * @return emptyInfo object
     */
    public static SyncInfo emptyInfo() {
      return EMPTY_INFO;
    }
  
    /**
     * Returns a list of sync points.
     *
     * @return a list of sync points
     */
    public Set<AlluxioURI> getSyncPoints() {
      return mChangedFilesMap.keySet();
    }
  
    /**
     * REturns a set of changed files.
     *
     * @param syncPoint the syncPoint that we are monitoring
     * @return a set of sync points
     */
    public Set<AlluxioURI> getChangedFiles(AlluxioURI syncPoint) {
      return mChangedFilesMap.get(syncPoint);
    }
  
    /**
     * returns true if this sync should happen on the entire directory.
     *
     * @return true if this sync should happen on the entire dir
     */
    public boolean isForceSync() {
      return mForceSync;
    }
  
    /**
     * returns the transaction id that is synced in this sync period.
     *
     * @return a transaction id that is synced in this sync period
     */
    public long getTxId() {
      return mTxId;
    }
  }
  