private void AddVarIntsField(FieldInfo field, IndexOutput output, IEnumerable <long?> values, long minValue, long maxValue)
{
field.PutAttribute(LegacyKey, LegacyDocValuesType.VAR_INTS.Name);
CodecUtil.WriteHeader(output, Lucene40DocValuesFormat.VAR_INTS_CODEC_NAME, Lucene40DocValuesFormat.VAR_INTS_VERSION_CURRENT);
long delta = maxValue - minValue;
if (delta < 0)
{
// writes longs
output.WriteByte((byte)Lucene40DocValuesFormat.VAR_INTS_FIXED_64);
foreach (long?n in values)
{
output.WriteLong(n == null ? 0 : n.Value);
}
}
else
{
// writes packed ints
output.WriteByte((byte)Lucene40DocValuesFormat.VAR_INTS_PACKED);
output.WriteLong(minValue);
output.WriteLong(0 - minValue); // default value (representation of 0)
PackedInts.Writer writer = PackedInts.GetWriter(output, State.SegmentInfo.DocCount, PackedInts.BitsRequired(delta), PackedInts.DEFAULT);
foreach (long?n in values)
{
long v = n == null ? 0 : (long)n;
writer.Add(v - minValue);
}
writer.Finish();
}
}
/// <summary> Save this segment's info.</summary>
internal void Write(IndexOutput output)
{
output.WriteString(name);
output.WriteInt(docCount);
output.WriteLong(delGen);
output.WriteInt(docStoreOffset);
if (docStoreOffset != -1)
{
output.WriteString(docStoreSegment);
output.WriteByte((byte)(docStoreIsCompoundFile?1:0));
}
output.WriteByte((byte)(hasSingleNormFile?1:0));
if (normGen == null)
{
output.WriteInt(NO);
}
else
{
output.WriteInt(normGen.Length);
for (int j = 0; j < normGen.Length; j++)
{
output.WriteLong(normGen[j]);
}
}
output.WriteByte((byte)isCompoundFile);
output.WriteInt(delCount);
output.WriteByte((byte)(hasProx?1:0));
output.WriteStringStringMap(diagnostics);
}
public override void StartDocument(int numVectorFields)
{
LastFieldName = null;
this.NumVectorFields = numVectorFields;
Tvx.WriteLong(Tvd.FilePointer);
Tvx.WriteLong(Tvf.FilePointer);
Tvd.WriteVInt(numVectorFields);
FieldCount = 0;
Fps = ArrayUtil.Grow(Fps, numVectorFields);
}
private void Initialize(Directory directory, string segment, FieldInfos fis, int interval, bool isi)
{
IndexInterval = interval;
FieldInfos = fis;
IsIndex = isi;
Output = directory.CreateOutput(IndexFileNames.SegmentFileName(segment, "", (IsIndex ? Lucene3xPostingsFormat.TERMS_INDEX_EXTENSION : Lucene3xPostingsFormat.TERMS_EXTENSION)), IOContext.DEFAULT);
bool success = false;
try
{
Output.WriteInt(FORMAT_CURRENT); // write format
Output.WriteLong(0); // leave space for size
Output.WriteInt(IndexInterval); // write indexInterval
Output.WriteInt(SkipInterval); // write skipInterval
Output.WriteInt(MaxSkipLevels); // write maxSkipLevels
Debug.Assert(InitUTF16Results());
success = true;
}
finally
{
if (!success)
{
IOUtils.CloseWhileHandlingException(Output);
try
{
directory.DeleteFile(IndexFileNames.SegmentFileName(segment, "", (IsIndex ? Lucene3xPostingsFormat.TERMS_INDEX_EXTENSION : Lucene3xPostingsFormat.TERMS_EXTENSION)));
}
catch (IOException ignored)
{
}
}
}
}
/// <summary>Fills in no-term-vectors for all docs we haven't seen
/// since the last doc that had term vectors.
/// </summary>
internal void Fill(int docID)
{
int docStoreOffset = docWriter.DocStoreOffset;
int end = docID + docStoreOffset;
if (lastDocID < end)
{
long tvfPosition = tvf.FilePointer;
while (lastDocID < end)
{
tvx.WriteLong(tvd.FilePointer);
tvd.WriteVInt(0);
tvx.WriteLong(tvfPosition);
lastDocID++;
}
}
}
private void AddVarSortedBytesField(FieldInfo field, IndexOutput data, IndexOutput index, IEnumerable <BytesRef> values, IEnumerable <long?> docToOrd)
{
field.PutAttribute(LegacyKey, LegacyDocValuesType.BYTES_VAR_SORTED.Name);
CodecUtil.WriteHeader(data, Lucene40DocValuesFormat.BYTES_VAR_SORTED_CODEC_NAME_DAT, Lucene40DocValuesFormat.BYTES_VAR_SORTED_VERSION_CURRENT);
CodecUtil.WriteHeader(index, Lucene40DocValuesFormat.BYTES_VAR_SORTED_CODEC_NAME_IDX, Lucene40DocValuesFormat.BYTES_VAR_SORTED_VERSION_CURRENT);
/* values */
long startPos = data.FilePointer;
int valueCount = 0;
foreach (BytesRef v in values)
{
data.WriteBytes(v.Bytes, v.Offset, v.Length);
valueCount++;
}
/* addresses */
long maxAddress = data.FilePointer - startPos;
index.WriteLong(maxAddress);
Debug.Assert(valueCount != int.MaxValue); // unsupported by the 4.0 impl
PackedInts.Writer w = PackedInts.GetWriter(index, valueCount + 1, PackedInts.BitsRequired(maxAddress), PackedInts.DEFAULT);
long currentPosition = 0;
foreach (BytesRef v in values)
{
w.Add(currentPosition);
currentPosition += v.Length;
}
// write sentinel
Debug.Assert(currentPosition == maxAddress);
w.Add(currentPosition);
w.Finish();
/* ordinals */
int maxDoc = State.SegmentInfo.DocCount;
Debug.Assert(valueCount > 0);
PackedInts.Writer ords = PackedInts.GetWriter(index, maxDoc, PackedInts.BitsRequired(valueCount - 1), PackedInts.DEFAULT);
foreach (long n in docToOrd)
{
ords.Add((long)n);
}
ords.Finish();
}
private void Initialize(Directory directory, System.String segment, FieldInfos fis, int interval, bool isi)
{
indexInterval = interval;
fieldInfos = fis;
isIndex = isi;
output = directory.CreateOutput(segment + (isIndex?".tii":".tis"));
output.WriteInt(FORMAT_CURRENT); // write format
output.WriteLong(0); // leave space for size
output.WriteInt(indexInterval); // write indexInterval
output.WriteInt(skipInterval); // write skipInterval
output.WriteInt(maxSkipLevels); // write maxSkipLevels
System.Diagnostics.Debug.Assert(InitUTF16Results());
}
/// <summary>Called to complete TermInfos creation. </summary>
public void Dispose()
{
// Move to protected method if class becomes unsealed
if (isDisposed)
{
return;
}
output.Seek(4); // write size after format
output.WriteLong(size);
output.Dispose();
if (!isIndex)
{
other.Dispose();
}
isDisposed = true;
}
private void AddVarDerefBytesField(FieldInfo field, IndexOutput data, IndexOutput index, IEnumerable <BytesRef> values)
{
field.PutAttribute(LegacyKey, LegacyDocValuesType.BYTES_VAR_DEREF.Name);
CodecUtil.WriteHeader(data, Lucene40DocValuesFormat.BYTES_VAR_DEREF_CODEC_NAME_DAT, Lucene40DocValuesFormat.BYTES_VAR_DEREF_VERSION_CURRENT);
CodecUtil.WriteHeader(index, Lucene40DocValuesFormat.BYTES_VAR_DEREF_CODEC_NAME_IDX, Lucene40DocValuesFormat.BYTES_VAR_DEREF_VERSION_CURRENT);
// deduplicate
SortedSet <BytesRef> dictionary = new SortedSet <BytesRef>();
foreach (BytesRef v in values)
{
dictionary.Add(v == null ? new BytesRef() : BytesRef.DeepCopyOf(v));
}
/* values */
long startPosition = data.FilePointer;
long currentAddress = 0;
Dictionary <BytesRef, long> valueToAddress = new Dictionary <BytesRef, long>();
foreach (BytesRef v in dictionary)
{
currentAddress = data.FilePointer - startPosition;
valueToAddress[v] = currentAddress;
WriteVShort(data, v.Length);
data.WriteBytes(v.Bytes, v.Offset, v.Length);
}
/* ordinals */
long totalBytes = data.FilePointer - startPosition;
index.WriteLong(totalBytes);
int maxDoc = State.SegmentInfo.DocCount;
PackedInts.Writer w = PackedInts.GetWriter(index, maxDoc, PackedInts.BitsRequired(currentAddress), PackedInts.DEFAULT);
foreach (BytesRef v in values)
{
w.Add(valueToAddress[v == null ? new BytesRef() : v]);
}
w.Finish();
}
/// <summary>
/// Called to complete TermInfos creation. </summary>
public void Dispose()
{
try
{
Output.Seek(4); // write size after format
Output.WriteLong(Size);
}
finally
{
try
{
Output.Dispose();
}
finally
{
if (!IsIndex)
{
Other.Dispose();
}
}
}
}
/// <summary>Merge files with the extensions added up to now.
/// All files with these extensions are combined sequentially into the
/// compound stream. After successful merge, the source files
/// are deleted.
/// </summary>
/// <throws> IllegalStateException if close() had been called before or </throws>
/// <summary> if no file has been added to this object
/// </summary>
public void Dispose()
{
// Extract into protected method if class ever becomes unsealed
// TODO: Dispose shouldn't throw exceptions!
if (merged)
{
throw new SystemException("Merge already performed");
}
if ((entries.Count == 0))
{
throw new SystemException("No entries to merge have been defined");
}
merged = true;
// open the compound stream
IndexOutput os = null;
try
{
os = directory.CreateOutput(fileName);
// Write the number of entries
os.WriteVInt(entries.Count);
// Write the directory with all offsets at 0.
// Remember the positions of directory entries so that we can
// adjust the offsets later
long totalSize = 0;
foreach (FileEntry fe in entries)
{
fe.directoryOffset = os.FilePointer;
os.WriteLong(0); // for now
os.WriteString(fe.file);
totalSize += directory.FileLength(fe.file);
}
// Pre-allocate size of file as optimization --
// this can potentially help IO performance as
// we write the file and also later during
// searching. It also uncovers a disk-full
// situation earlier and hopefully without
// actually filling disk to 100%:
long finalLength = totalSize + os.FilePointer;
os.SetLength(finalLength);
// Open the files and copy their data into the stream.
// Remember the locations of each file's data section.
var buffer = new byte[16384];
foreach (FileEntry fe in entries)
{
fe.dataOffset = os.FilePointer;
CopyFile(fe, os, buffer);
}
// Write the data offsets into the directory of the compound stream
foreach (FileEntry fe in entries)
{
os.Seek(fe.directoryOffset);
os.WriteLong(fe.dataOffset);
}
System.Diagnostics.Debug.Assert(finalLength == os.Length);
// Close the output stream. Set the os to null before trying to
// close so that if an exception occurs during the close, the
// finally clause below will not attempt to close the stream
// the second time.
IndexOutput tmp = os;
os = null;
tmp.Close();
}
finally
{
if (os != null)
{
try
{
os.Close();
}
catch (System.IO.IOException)
{
}
}
}
}
/// <summary> Add a complete document specified by all its term vectors. If document has no
/// term vectors, add value for tvx.
///
/// </summary>
/// <param name="vectors">
/// </param>
/// <throws> IOException </throws>
public void AddAllDocVectors(ITermFreqVector[] vectors)
{
tvx.WriteLong(tvd.FilePointer);
tvx.WriteLong(tvf.FilePointer);
if (vectors != null)
{
int numFields = vectors.Length;
tvd.WriteVInt(numFields);
var fieldPointers = new long[numFields];
for (int i = 0; i < numFields; i++)
{
fieldPointers[i] = tvf.FilePointer;
int fieldNumber = fieldInfos.FieldNumber(vectors[i].Field);
// 1st pass: write field numbers to tvd
tvd.WriteVInt(fieldNumber);
int numTerms = vectors[i].Size;
tvf.WriteVInt(numTerms);
TermPositionVector tpVector;
byte bits;
bool storePositions;
bool storeOffsets;
if (vectors[i] is TermPositionVector)
{
// May have positions & offsets
tpVector = (TermPositionVector)vectors[i];
storePositions = tpVector.Size > 0 && tpVector.GetTermPositions(0) != null;
storeOffsets = tpVector.Size > 0 && tpVector.GetOffsets(0) != null;
bits = (byte)((storePositions?TermVectorsReader.STORE_POSITIONS_WITH_TERMVECTOR: (byte)0) + (storeOffsets?TermVectorsReader.STORE_OFFSET_WITH_TERMVECTOR: (byte)0));
}
else
{
tpVector = null;
bits = 0;
storePositions = false;
storeOffsets = false;
}
tvf.WriteVInt(bits);
System.String[] terms = vectors[i].GetTerms();
int[] freqs = vectors[i].GetTermFrequencies();
int utf8Upto = 0;
utf8Results[1].length = 0;
for (int j = 0; j < numTerms; j++)
{
UnicodeUtil.UTF16toUTF8(terms[j], 0, terms[j].Length, utf8Results[utf8Upto]);
int start = StringHelper.BytesDifference(utf8Results[1 - utf8Upto].result, utf8Results[1 - utf8Upto].length, utf8Results[utf8Upto].result, utf8Results[utf8Upto].length);
int length = utf8Results[utf8Upto].length - start;
tvf.WriteVInt(start); // write shared prefix length
tvf.WriteVInt(length); // write delta length
tvf.WriteBytes(utf8Results[utf8Upto].result, start, length); // write delta bytes
utf8Upto = 1 - utf8Upto;
int termFreq = freqs[j];
tvf.WriteVInt(termFreq);
if (storePositions)
{
int[] positions = tpVector.GetTermPositions(j);
if (positions == null)
{
throw new System.SystemException("Trying to write positions that are null!");
}
System.Diagnostics.Debug.Assert(positions.Length == termFreq);
// use delta encoding for positions
int lastPosition = 0;
foreach (int position in positions)
{
tvf.WriteVInt(position - lastPosition);
lastPosition = position;
}
}
if (storeOffsets)
{
TermVectorOffsetInfo[] offsets = tpVector.GetOffsets(j);
if (offsets == null)
{
throw new System.SystemException("Trying to write offsets that are null!");
}
System.Diagnostics.Debug.Assert(offsets.Length == termFreq);
// use delta encoding for offsets
int lastEndOffset = 0;
foreach (TermVectorOffsetInfo t in offsets)
{
int startOffset = t.StartOffset;
int endOffset = t.EndOffset;
tvf.WriteVInt(startOffset - lastEndOffset);
tvf.WriteVInt(endOffset - startOffset);
lastEndOffset = endOffset;
}
}
}
}
// 2nd pass: write field pointers to tvd
if (numFields > 1)
{
long lastFieldPointer = fieldPointers[0];
for (int i = 1; i < numFields; i++)
{
long fieldPointer = fieldPointers[i];
tvd.WriteVLong(fieldPointer - lastFieldPointer);
lastFieldPointer = fieldPointer;
}
}
}
else
{
tvd.WriteVInt(0);
}
}
public override void Write(Directory directory, string segmentName, string segmentSuffix, FieldInfos infos, IOContext context)
{
string fileName = IndexFileNames.SegmentFileName(segmentName, segmentSuffix, Lucene46FieldInfosFormat.EXTENSION);
IndexOutput output = directory.CreateOutput(fileName, context);
bool success = false;
try
{
CodecUtil.WriteHeader(output, Lucene46FieldInfosFormat.CODEC_NAME, Lucene46FieldInfosFormat.FORMAT_CURRENT);
output.WriteVInt(infos.Size());
foreach (FieldInfo fi in infos)
{
FieldInfo.IndexOptions?indexOptions = fi.FieldIndexOptions;
sbyte bits = 0x0;
if (fi.HasVectors())
{
bits |= Lucene46FieldInfosFormat.STORE_TERMVECTOR;
}
if (fi.OmitsNorms())
{
bits |= Lucene46FieldInfosFormat.OMIT_NORMS;
}
if (fi.HasPayloads())
{
bits |= Lucene46FieldInfosFormat.STORE_PAYLOADS;
}
if (fi.Indexed)
{
bits |= Lucene46FieldInfosFormat.IS_INDEXED;
Debug.Assert(indexOptions >= FieldInfo.IndexOptions.DOCS_AND_FREQS_AND_POSITIONS || !fi.HasPayloads());
if (indexOptions == FieldInfo.IndexOptions.DOCS_ONLY)
{
bits |= Lucene46FieldInfosFormat.OMIT_TERM_FREQ_AND_POSITIONS;
}
else if (indexOptions == FieldInfo.IndexOptions.DOCS_AND_FREQS_AND_POSITIONS_AND_OFFSETS)
{
bits |= Lucene46FieldInfosFormat.STORE_OFFSETS_IN_POSTINGS;
}
else if (indexOptions == FieldInfo.IndexOptions.DOCS_AND_FREQS)
{
bits |= Lucene46FieldInfosFormat.OMIT_POSITIONS;
}
}
output.WriteString(fi.Name);
output.WriteVInt(fi.Number);
output.WriteByte((byte)bits);
// pack the DV types in one byte
var dv = DocValuesByte(fi.DocValuesType);
var nrm = DocValuesByte(fi.NormType);
Debug.Assert((dv & (~0xF)) == 0 && (nrm & (~0x0F)) == 0);
var val = unchecked ((sbyte)(0xff & ((nrm << 4) | dv)));
output.WriteByte((byte)val);
output.WriteLong(fi.DocValuesGen);
output.WriteStringStringMap(fi.Attributes());
}
CodecUtil.WriteFooter(output);
success = true;
}
finally
{
if (success)
{
output.Dispose();
}
else
{
IOUtils.CloseWhileHandlingException(output);
}
}
}
private static void WriteTrailer(IndexOutput output, long dirStart)
{
output.WriteLong(dirStart);
}
public override void WriteField(FieldInfo info, IndexableField field)
{
FieldsStream.WriteVInt(info.Number);
int bits = 0;
BytesRef bytes;
string @string;
// TODO: maybe a field should serialize itself?
// this way we don't bake into indexer all these
// specific encodings for different fields? and apps
// can customize...
object number = (object)field.NumericValue;
if (number != null)
{
if (number is sbyte || number is short || number is int)
{
bits |= FIELD_IS_NUMERIC_INT;
}
else if (number is long)
{
bits |= FIELD_IS_NUMERIC_LONG;
}
else if (number is float)
{
bits |= FIELD_IS_NUMERIC_FLOAT;
}
else if (number is double)
{
bits |= FIELD_IS_NUMERIC_DOUBLE;
}
else
{
throw new System.ArgumentException("cannot store numeric type " + number.GetType());
}
@string = null;
bytes = null;
}
else
{
bytes = field.BinaryValue();
if (bytes != null)
{
bits |= FIELD_IS_BINARY;
@string = null;
}
else
{
@string = field.StringValue;
if (@string == null)
{
throw new System.ArgumentException("field " + field.Name() + " is stored but does not have binaryValue, stringValue nor numericValue");
}
}
}
FieldsStream.WriteByte((byte)(sbyte)bits);
if (bytes != null)
{
FieldsStream.WriteVInt(bytes.Length);
FieldsStream.WriteBytes(bytes.Bytes, bytes.Offset, bytes.Length);
}
else if (@string != null)
{
FieldsStream.WriteString(field.StringValue);
}
else
{
if (number is sbyte || number is short || number is int)
{
FieldsStream.WriteInt((int)number);
}
else if (number is long)
{
FieldsStream.WriteLong((long)number);
}
else if (number is float)
{
FieldsStream.WriteInt(Number.FloatToIntBits((float)number));
}
else if (number is double)
{
FieldsStream.WriteLong(BitConverter.DoubleToInt64Bits((double)number));
}
else
{
throw new InvalidOperationException("Cannot get here");
}
}
}
// Writes the contents of buffer into the fields stream
// and adds a new entry for this document into the index
// stream. this assumes the buffer was already written
// in the correct fields format.
public override void StartDocument(int numStoredFields)
{
IndexStream.WriteLong(FieldsStream.FilePointer);
FieldsStream.WriteVInt(numStoredFields);
}
public override void AddNumericField(FieldInfo field, IEnumerable <long?> values)
{
Meta.WriteVInt(field.Number);
Meta.WriteByte((byte)NUMBER);
Meta.WriteLong(Data.FilePointer);
long minValue = long.MaxValue;
long maxValue = long.MinValue;
long gcd = 0;
// TODO: more efficient?
HashSet <long> uniqueValues = null;
if (true)
{
uniqueValues = new HashSet <long>();
long count = 0;
foreach (long?nv in values)
{
Debug.Assert(nv != null);
long v = nv.Value;
if (gcd != 1)
{
if (v < long.MinValue / 2 || v > long.MaxValue / 2)
{
// in that case v - minValue might overflow and make the GCD computation return
// wrong results. Since these extreme values are unlikely, we just discard
// GCD computation for them
gcd = 1;
} // minValue needs to be set first
else if (count != 0)
{
gcd = MathUtil.Gcd(gcd, v - minValue);
}
}
minValue = Math.Min(minValue, v);
maxValue = Math.Max(maxValue, v);
if (uniqueValues != null)
{
if (uniqueValues.Add(v))
{
if (uniqueValues.Count > 256)
{
uniqueValues = null;
}
}
}
++count;
}
Debug.Assert(count == MaxDoc);
}
if (uniqueValues != null)
{
// small number of unique values
int bitsPerValue = PackedInts.BitsRequired(uniqueValues.Count - 1);
FormatAndBits formatAndBits = PackedInts.FastestFormatAndBits(MaxDoc, bitsPerValue, AcceptableOverheadRatio);
if (formatAndBits.bitsPerValue == 8 && minValue >= sbyte.MinValue && maxValue <= sbyte.MaxValue)
{
Meta.WriteByte((byte)UNCOMPRESSED); // uncompressed
foreach (long?nv in values)
{
Data.WriteByte(nv == null ? (byte)0 : (byte)(sbyte)nv.Value);
}
}
else
{
Meta.WriteByte((byte)TABLE_COMPRESSED); // table-compressed
//LUCENE TO-DO, ToArray had a parameter to start
var decode = uniqueValues.ToArray();
var encode = new Dictionary <long, int>();
Data.WriteVInt(decode.Length);
for (int i = 0; i < decode.Length; i++)
{
Data.WriteLong(decode[i]);
encode[decode[i]] = i;
}
Meta.WriteVInt(PackedInts.VERSION_CURRENT);
Data.WriteVInt(formatAndBits.format.id);
Data.WriteVInt(formatAndBits.bitsPerValue);
PackedInts.Writer writer = PackedInts.GetWriterNoHeader(Data, formatAndBits.format, MaxDoc, formatAndBits.bitsPerValue, PackedInts.DEFAULT_BUFFER_SIZE);
foreach (long?nv in values)
{
writer.Add(encode[nv == null ? 0 : nv.Value]);
}
writer.Finish();
}
}
else if (gcd != 0 && gcd != 1)
{
Meta.WriteByte((byte)GCD_COMPRESSED);
Meta.WriteVInt(PackedInts.VERSION_CURRENT);
Data.WriteLong(minValue);
Data.WriteLong(gcd);
Data.WriteVInt(BLOCK_SIZE);
var writer = new BlockPackedWriter(Data, BLOCK_SIZE);
foreach (long?nv in values)
{
long value = nv == null ? 0 : nv.Value;
writer.Add((value - minValue) / gcd);
}
writer.Finish();
}
else
{
Meta.WriteByte((byte)DELTA_COMPRESSED); // delta-compressed
Meta.WriteVInt(PackedInts.VERSION_CURRENT);
Data.WriteVInt(BLOCK_SIZE);
var writer = new BlockPackedWriter(Data, BLOCK_SIZE);
foreach (long?nv in values)
{
writer.Add(nv == null ? 0 : nv.Value);
}
writer.Finish();
}
}
// Writes the contents of buffer into the fields stream
// and adds a new entry for this document into the index
// stream. This assumes the buffer was already written
// in the correct fields format.
internal void FlushDocument(int numStoredFields, RAMOutputStream buffer)
{
indexStream.WriteLong(fieldsStream.FilePointer);
fieldsStream.WriteVInt(numStoredFields);
buffer.WriteTo(fieldsStream);
}
internal void FinishCommit(Directory dir)
{
if (pendingSegnOutput == null)
{
throw new System.SystemException("prepareCommit was not called");
}
bool 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.
System.String fileName = IndexFileNames.FileNameFromGeneration(IndexFileNames.SEGMENTS, "", generation);
success = false;
try
{
dir.Sync(fileName);
success = true;
}
finally
{
if (!success)
{
try
{
dir.DeleteFile(fileName);
}
catch (System.Exception)
{
// 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 (System.Exception)
{
// It's OK if we fail to write this file since it's
// used only as one of the retry fallbacks.
}
}
/// <summary>
/// Writes a codec footer, which records both a checksum
/// algorithm ID and a checksum. this footer can
/// be parsed and validated with
/// <seealso cref="#checkFooter(ChecksumIndexInput) checkFooter()"/>.
/// <p>
/// CodecFooter --> Magic,AlgorithmID,Checksum
/// <ul>
/// <li>Magic --> <seealso cref="DataOutput#writeInt Uint32"/>. this
/// identifies the start of the footer. It is always {@value #FOOTER_MAGIC}.
/// <li>AlgorithmID --> <seealso cref="DataOutput#writeInt Uint32"/>. this
/// indicates the checksum algorithm used. Currently this is always 0,
/// for zlib-crc32.
/// <li>Checksum --> <seealso cref="DataOutput#writeLong Uint32"/>. The
/// actual checksum value for all previous bytes in the stream, including
/// the bytes from Magic and AlgorithmID.
/// </ul>
/// </summary>
/// <param name="out"> Output stream </param>
/// <exception cref="IOException"> If there is an I/O error writing to the underlying medium. </exception>
public static void WriteFooter(IndexOutput @out)
{
@out.WriteInt(FOOTER_MAGIC);
@out.WriteInt(0);
@out.WriteLong(@out.Checksum);
}
private void WriteTrailer(long dirStart)
{
Output.WriteLong(dirStart);
}
private static void WriteTrailer(IndexOutput output, long dirStart)
{
output.WriteLong(dirStart);
}
