final void finishCommit(Directory dir) throws IOException {
if (pendingSegnOutput == null) throw new IllegalStateException("prepareCommit was not called");
boolean success = false;
try {
pendingSegnOutput.finishCommit();
pendingSegnOutput.close();
pendingSegnOutput = null;
success = true;
} finally {
if (!success) rollbackCommit(dir);
}
// NOTE: if we crash here, we have left a segments_N
// file in the directory in a possibly corrupt state (if
// some bytes made it to stable storage and others
// didn't). But, the segments_N file includes checksum
// at the end, which should catch this case. So when a
// reader tries to read it, it will throw a
// CorruptIndexException, which should cause the retry
// logic in SegmentInfos to kick in and load the last
// good (previous) segments_N-1 file.
final String fileName =
IndexFileNames.fileNameFromGeneration(IndexFileNames.SEGMENTS, "", generation);
success = false;
try {
dir.sync(Collections.singleton(fileName));
success = true;
} finally {
if (!success) {
try {
dir.deleteFile(fileName);
} catch (Throwable t) {
// Suppress so we keep throwing the original exception
}
}
}
lastGeneration = generation;
try {
IndexOutput genOutput = dir.createOutput(IndexFileNames.SEGMENTS_GEN);
try {
genOutput.writeInt(FORMAT_LOCKLESS);
genOutput.writeLong(generation);
genOutput.writeLong(generation);
} finally {
genOutput.close();
}
} catch (ThreadInterruptedException t) {
throw t;
} catch (Throwable t) {
// It's OK if we fail to write this file since it's
// used only as one of the retry fallbacks.
}
}
@Override
public void sync(Collection<String> names) throws IOException {
fsDir.sync(names);
}
/**
* 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).
*
* @throws IOException if there is a low-level IO error
*/
@Override
protected void doCommit(Map<String, String> commitUserData) throws IOException {
if (hasChanges) {
segmentInfos.setUserData(commitUserData);
// Default deleter (for backwards compatibility) is
// KeepOnlyLastCommitDeleter:
IndexFileDeleter deleter =
new IndexFileDeleter(
directory,
deletionPolicy == null ? new KeepOnlyLastCommitDeletionPolicy() : deletionPolicy,
segmentInfos,
null,
null);
segmentInfos.updateGeneration(deleter.getLastSegmentInfos());
segmentInfos.changed();
// Checkpoint the state we are about to change, in
// case we have to roll back:
startCommit();
final List<SegmentInfo> rollbackSegments = segmentInfos.createBackupSegmentInfos(false);
boolean success = false;
try {
for (int i = 0; i < subReaders.length; i++) subReaders[i].commit();
// Remove segments that contain only 100% deleted
// docs:
segmentInfos.pruneDeletedSegments();
// Sync all files we just wrote
directory.sync(segmentInfos.files(directory, false));
segmentInfos.commit(directory);
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();
// Restore all SegmentInfos (in case we pruned some)
segmentInfos.rollbackSegmentInfos(rollbackSegments);
}
}
// Have the deleter remove any now unreferenced
// files due to this commit:
deleter.checkpoint(segmentInfos, true);
deleter.close();
maxIndexVersion = segmentInfos.getVersion();
if (writeLock != null) {
writeLock.release(); // release write lock
writeLock = null;
}
}
hasChanges = false;
}
private void write(Directory directory) throws IOException {
long nextGeneration = getNextPendingGeneration();
String segmentFileName =
IndexFileNames.fileNameFromGeneration(IndexFileNames.PENDING_SEGMENTS, "", nextGeneration);
// Always advance the generation on write:
generation = nextGeneration;
IndexOutput segnOutput = null;
boolean success = false;
try {
segnOutput = directory.createOutput(segmentFileName, IOContext.DEFAULT);
CodecUtil.writeIndexHeader(
segnOutput,
"segments",
VERSION_CURRENT,
StringHelper.randomId(),
Long.toString(nextGeneration, Character.MAX_RADIX));
segnOutput.writeVInt(Version.LATEST.major);
segnOutput.writeVInt(Version.LATEST.minor);
segnOutput.writeVInt(Version.LATEST.bugfix);
segnOutput.writeLong(version);
segnOutput.writeInt(counter); // write counter
segnOutput.writeInt(size());
if (size() > 0) {
Version minSegmentVersion = null;
// We do a separate loop up front so we can write the minSegmentVersion before
// any SegmentInfo; this makes it cleaner to throw IndexFormatTooOldExc at read time:
for (SegmentCommitInfo siPerCommit : this) {
Version segmentVersion = siPerCommit.info.getVersion();
if (minSegmentVersion == null || segmentVersion.onOrAfter(minSegmentVersion) == false) {
minSegmentVersion = segmentVersion;
}
}
segnOutput.writeVInt(minSegmentVersion.major);
segnOutput.writeVInt(minSegmentVersion.minor);
segnOutput.writeVInt(minSegmentVersion.bugfix);
}
// write infos
for (SegmentCommitInfo siPerCommit : this) {
SegmentInfo si = siPerCommit.info;
segnOutput.writeString(si.name);
byte segmentID[] = si.getId();
// TODO: remove this in lucene 6, we don't need to include 4.x segments in commits anymore
if (segmentID == null) {
segnOutput.writeByte((byte) 0);
} else {
if (segmentID.length != StringHelper.ID_LENGTH) {
throw new IllegalStateException(
"cannot write segment: invalid id segment="
+ si.name
+ "id="
+ StringHelper.idToString(segmentID));
}
segnOutput.writeByte((byte) 1);
segnOutput.writeBytes(segmentID, segmentID.length);
}
segnOutput.writeString(si.getCodec().getName());
segnOutput.writeLong(siPerCommit.getDelGen());
int delCount = siPerCommit.getDelCount();
if (delCount < 0 || delCount > si.maxDoc()) {
throw new IllegalStateException(
"cannot write segment: invalid maxDoc segment="
+ si.name
+ " maxDoc="
+ si.maxDoc()
+ " delCount="
+ delCount);
}
segnOutput.writeInt(delCount);
segnOutput.writeLong(siPerCommit.getFieldInfosGen());
segnOutput.writeLong(siPerCommit.getDocValuesGen());
segnOutput.writeSetOfStrings(siPerCommit.getFieldInfosFiles());
final Map<Integer, Set<String>> dvUpdatesFiles = siPerCommit.getDocValuesUpdatesFiles();
segnOutput.writeInt(dvUpdatesFiles.size());
for (Entry<Integer, Set<String>> e : dvUpdatesFiles.entrySet()) {
segnOutput.writeInt(e.getKey());
segnOutput.writeSetOfStrings(e.getValue());
}
}
segnOutput.writeMapOfStrings(userData);
CodecUtil.writeFooter(segnOutput);
segnOutput.close();
directory.sync(Collections.singleton(segmentFileName));
success = true;
} finally {
if (success) {
pendingCommit = true;
} else {
// We hit an exception above; try to close the file
// but suppress any exception:
IOUtils.closeWhileHandlingException(segnOutput);
// Try not to leave a truncated segments_N file in
// the index:
IOUtils.deleteFilesIgnoringExceptions(directory, segmentFileName);
}
}
}