/// <summary> /// <inheritDoc/> /// <br/> /// To destroy a DstReference node, we first remove its link with the /// referred node. If the reference number of the referred node is <= 0, we /// destroy the subtree of the referred node. Otherwise, we clean the /// referred node's subtree and delete everything created after the last /// rename operation, i.e., everything outside of the scope of the prior /// WithName nodes. /// </summary> public override void DestroyAndCollectBlocks(BlockStoragePolicySuite bsps, INode.BlocksMapUpdateInfo collectedBlocks, IList <INode> removedINodes) { if (RemoveReference(this) <= 0) { GetReferredINode().DestroyAndCollectBlocks(bsps, collectedBlocks, removedINodes); } else { // we will clean everything, including files, directories, and // snapshots, that were created after this prior snapshot int prior = GetPriorSnapshot(this); // prior must be non-null, otherwise we do not have any previous // WithName nodes, and the reference number will be 0. Preconditions.CheckState(prior != Org.Apache.Hadoop.Hdfs.Server.Namenode.Snapshot.Snapshot .NoSnapshotId); // identify the snapshot created after prior int snapshot = GetSelfSnapshot(prior); INode referred = GetReferredINode().AsReference().GetReferredINode(); if (referred.IsFile()) { // if referred is a file, it must be a file with snapshot since we did // recordModification before the rename INodeFile file = referred.AsFile(); Preconditions.CheckState(file.IsWithSnapshot()); // make sure we mark the file as deleted file.GetFileWithSnapshotFeature().DeleteCurrentFile(); // when calling cleanSubtree of the referred node, since we // compute quota usage updates before calling this destroy // function, we use true for countDiffChange referred.CleanSubtree(bsps, snapshot, prior, collectedBlocks, removedINodes); } else { if (referred.IsDirectory()) { // similarly, if referred is a directory, it must be an // INodeDirectory with snapshot INodeDirectory dir = referred.AsDirectory(); Preconditions.CheckState(dir.IsWithSnapshot()); try { DirectoryWithSnapshotFeature.DestroyDstSubtree(bsps, dir, snapshot, prior, collectedBlocks , removedINodes); } catch (QuotaExceededException e) { Log.Error("should not exceed quota while snapshot deletion", e); } } } } }