private void Init(Directory d, Analyzer a, bool create, IndexDeletionPolicy deletionPolicy, int maxFieldLength, DocumentsWriter.IndexingChain indexingChain, IndexCommit commit) { directory = d; analyzer = a; SetMessageID(defaultInfoStream); this.maxFieldLength = maxFieldLength; if (indexingChain == null) indexingChain = DocumentsWriter.DefaultIndexingChain; if (create) { // Clear the write lock in case it's leftover: directory.ClearLock(WRITE_LOCK_NAME); } Lock writeLock = directory.MakeLock(WRITE_LOCK_NAME); if (!writeLock.Obtain(writeLockTimeout)) // obtain write lock { throw new LockObtainFailedException("Index locked for write: " + writeLock); } this.writeLock = writeLock; // save it bool success = false; try { if (create) { // Try to read first. This is to allow create // against an index that's currently open for // searching. In this case we write the next // segments_N file with no segments: bool doCommit; try { segmentInfos.Read(directory); segmentInfos.Clear(); doCommit = false; } catch (System.IO.IOException) { // Likely this means it's a fresh directory doCommit = true; } if (doCommit) { // Only commit if there is no segments file // in this dir already. segmentInfos.Commit(directory); synced.UnionWith(segmentInfos.Files(directory, true)); } else { // Record that we have a change (zero out all // segments) pending: changeCount++; } } else { segmentInfos.Read(directory); if (commit != null) { // Swap out all segments, but, keep metadata in // SegmentInfos, like version & generation, to // preserve write-once. This is important if // readers are open against the future commit // points. if (commit.Directory != directory) throw new System.ArgumentException("IndexCommit's directory doesn't match my directory"); SegmentInfos oldInfos = new SegmentInfos(); oldInfos.Read(directory, commit.SegmentsFileName); segmentInfos.Replace(oldInfos); changeCount++; if (infoStream != null) Message("init: loaded commit \"" + commit.SegmentsFileName + "\""); } // We assume that this segments_N was previously // properly sync'd: synced.UnionWith(segmentInfos.Files(directory, true)); } SetRollbackSegmentInfos(segmentInfos); docWriter = new DocumentsWriter(directory, this, indexingChain); docWriter.SetInfoStream(infoStream); docWriter.SetMaxFieldLength(maxFieldLength); // Default deleter (for backwards compatibility) is // KeepOnlyLastCommitDeleter: deleter = new IndexFileDeleter(directory, deletionPolicy == null?new KeepOnlyLastCommitDeletionPolicy():deletionPolicy, segmentInfos, infoStream, docWriter, synced); if (deleter.startingCommitDeleted) // Deletion policy deleted the "head" commit point. // We have to mark ourself as changed so that if we // are closed w/o any further changes we write a new // segments_N file. changeCount++; PushMaxBufferedDocs(); if (infoStream != null) { Message("init: create=" + create); MessageState(); } success = true; } finally { if (!success) { if (infoStream != null) { Message("init: hit exception on init; releasing write lock"); } try { writeLock.Release(); } catch (Exception) { // don't mask the original exception } writeLock = null; } } }
/// <summary> Commit changes resulting from delete, undeleteAll, or setNorm operations /// <p/> /// If an exception is hit, then either no changes or all changes will have been committed to the index (transactional /// semantics). /// /// </summary> /// <throws> IOException if there is a low-level IO error </throws> protected internal override void DoCommit(IDictionary<string, string> commitUserData) { if (hasChanges) { segmentInfos.UserData = commitUserData; // Default deleter (for backwards compatibility) is // KeepOnlyLastCommitDeleter: var deleter = new IndexFileDeleter(internalDirectory, deletionPolicy ?? new KeepOnlyLastCommitDeletionPolicy(), segmentInfos, null, null, synced); segmentInfos.UpdateGeneration(deleter.LastSegmentInfos); // Checkpoint the state we are about to change, in // case we have to roll back: StartCommit(); bool success = false; try { foreach (SegmentReader t in subReaders) t.Commit(); // Sync all files we just wrote foreach(string fileName in segmentInfos.Files(internalDirectory, false)) { if(!synced.Contains(fileName)) { System.Diagnostics.Debug.Assert(internalDirectory.FileExists(fileName)); internalDirectory.Sync(fileName); synced.Add(fileName); } } segmentInfos.Commit(internalDirectory); success = true; } finally { if (!success) { // Rollback changes that were made to // SegmentInfos but failed to get [fully] // committed. This way this reader instance // remains consistent (matched to what's // actually in the index): RollbackCommit(); // Recompute deletable files & remove them (so // partially written .del files, etc, are // removed): deleter.Refresh(); } } // Have the deleter remove any now unreferenced // files due to this commit: deleter.Checkpoint(segmentInfos, true); deleter.Dispose(); maxIndexVersion = segmentInfos.Version; if (writeLock != null) { writeLock.Release(); // release write lock writeLock = null; } } hasChanges = false; }