/// <summary>
            /// Go to the chunk containing the provided doc ID.
            /// </summary>
            internal void Next(int doc)
            {
                Debug.Assert(doc >= DocBase + ChunkDocs, doc + " " + DocBase + " " + ChunkDocs);
                FieldsStream.Seek(OuterInstance.IndexReader.GetStartPointer(doc));

                int docBase   = FieldsStream.ReadVInt();
                int chunkDocs = FieldsStream.ReadVInt();

                if (docBase < this.DocBase + this.ChunkDocs || docBase + chunkDocs > OuterInstance.NumDocs)
                {
                    throw new CorruptIndexException("Corrupted: current docBase=" + this.DocBase + ", current numDocs=" + this.ChunkDocs + ", new docBase=" + docBase + ", new numDocs=" + chunkDocs + " (resource=" + FieldsStream + ")");
                }
                this.DocBase   = docBase;
                this.ChunkDocs = chunkDocs;

                if (chunkDocs > NumStoredFields.Length)
                {
                    int newLength = ArrayUtil.Oversize(chunkDocs, 4);
                    NumStoredFields = new int[newLength];
                    Lengths         = new int[newLength];
                }

                if (chunkDocs == 1)
                {
                    NumStoredFields[0] = FieldsStream.ReadVInt();
                    Lengths[0]         = FieldsStream.ReadVInt();
                }
                else
                {
                    int bitsPerStoredFields = FieldsStream.ReadVInt();
                    if (bitsPerStoredFields == 0)
                    {
                        CollectionsHelper.Fill(NumStoredFields, 0, chunkDocs, FieldsStream.ReadVInt());
                    }
                    else if (bitsPerStoredFields > 31)
                    {
                        throw new CorruptIndexException("bitsPerStoredFields=" + bitsPerStoredFields + " (resource=" + FieldsStream + ")");
                    }
                    else
                    {
                        PackedInts.ReaderIterator it = PackedInts.GetReaderIteratorNoHeader(FieldsStream, PackedInts.Format.PACKED, OuterInstance.PackedIntsVersion, chunkDocs, bitsPerStoredFields, 1);
                        for (int i = 0; i < chunkDocs; ++i)
                        {
                            NumStoredFields[i] = (int)it.Next();
                        }
                    }

                    int bitsPerLength = FieldsStream.ReadVInt();
                    if (bitsPerLength == 0)
                    {
                        CollectionsHelper.Fill(Lengths, 0, chunkDocs, FieldsStream.ReadVInt());
                    }
                    else if (bitsPerLength > 31)
                    {
                        throw new CorruptIndexException("bitsPerLength=" + bitsPerLength);
                    }
                    else
                    {
                        PackedInts.ReaderIterator it = PackedInts.GetReaderIteratorNoHeader(FieldsStream, PackedInts.Format.PACKED, OuterInstance.PackedIntsVersion, chunkDocs, bitsPerLength, 1);
                        for (int i = 0; i < chunkDocs; ++i)
                        {
                            Lengths[i] = (int)it.Next();
                        }
                    }
                }
            }
Ejemplo n.º 2
0
                public CoreFieldIndex(long indexStart, long termsStart, long packedIndexStart, long packedOffsetsStart,
                                      int numIndexTerms, FixedGapTermsIndexReader fgtir)
                {
                    TermsStart     = termsStart;
                    TermBytesStart = fgtir._termBytes.Pointer;

                    var clone = (IndexInput)fgtir._input.Clone();

                    clone.Seek(indexStart);

                    // -1 is passed to mean "don't load term index", but
                    // if we are then later loaded it's overwritten with
                    // a real value
                    Debug.Assert(fgtir._indexDivisor > 0);

                    NumIndexTerms = 1 + (numIndexTerms - 1) / fgtir._indexDivisor;

                    Debug.Assert(NumIndexTerms > 0,
                                 String.Format("NumIndexTerms: {0}, IndexDivisor: {1}", NumIndexTerms, fgtir._indexDivisor));

                    if (fgtir._indexDivisor == 1)
                    {
                        // Default (load all index terms) is fast -- slurp in the images from disk:

                        try
                        {
                            var numTermBytes = packedIndexStart - indexStart;
                            fgtir._termBytes.Copy(clone, numTermBytes);

                            // records offsets into main terms dict file
                            TermsDictOffsets = PackedInts.GetReader(clone);
                            Debug.Assert(TermsDictOffsets.Size() == numIndexTerms);

                            // records offsets into byte[] term data
                            TermOffsets = PackedInts.GetReader(clone);
                            Debug.Assert(TermOffsets.Size() == 1 + numIndexTerms);
                        }
                        finally
                        {
                            clone.Dispose();
                        }
                    }
                    else
                    {
                        // Get packed iterators
                        var clone1 = (IndexInput)fgtir._input.Clone();
                        var clone2 = (IndexInput)fgtir._input.Clone();

                        try
                        {
                            // Subsample the index terms
                            clone1.Seek(packedIndexStart);

                            PackedInts.ReaderIterator termsDictOffsetsIter = PackedInts.GetReaderIterator(clone1,
                                                                                                          PackedInts.DEFAULT_BUFFER_SIZE);

                            clone2.Seek(packedOffsetsStart);

                            PackedInts.ReaderIterator termOffsetsIter = PackedInts.GetReaderIterator(clone2,
                                                                                                     PackedInts.DEFAULT_BUFFER_SIZE);

                            // TODO: often we can get by w/ fewer bits per
                            // value, below.. .but this'd be more complex:
                            // we'd have to try @ fewer bits and then grow
                            // if we overflowed it.

                            PackedInts.Mutable termsDictOffsetsM = PackedInts.GetMutable(NumIndexTerms,
                                                                                         termsDictOffsetsIter.BitsPerValue, PackedInts.DEFAULT);
                            PackedInts.Mutable termOffsetsM = PackedInts.GetMutable(NumIndexTerms + 1,
                                                                                    termOffsetsIter.BitsPerValue, PackedInts.DEFAULT);

                            TermsDictOffsets = termsDictOffsetsM;
                            TermOffsets      = termOffsetsM;

                            var  upto           = 0;
                            long termOffsetUpto = 0;

                            while (upto < NumIndexTerms)
                            {
                                // main file offset copies straight over
                                termsDictOffsetsM.Set(upto, termsDictOffsetsIter.Next());

                                termOffsetsM.Set(upto, termOffsetUpto);

                                var termOffset     = termOffsetsIter.Next();
                                var nextTermOffset = termOffsetsIter.Next();
                                var numTermBytes   = (int)(nextTermOffset - termOffset);

                                clone.Seek(indexStart + termOffset);

                                Debug.Assert(indexStart + termOffset < clone.Length(),
                                             String.Format("IndexStart: {0}, TermOffset: {1}, Len: {2}", indexStart, termOffset,
                                                           clone.Length()));

                                Debug.Assert(indexStart + termOffset + numTermBytes < clone.Length());

                                fgtir._termBytes.Copy(clone, numTermBytes);
                                termOffsetUpto += numTermBytes;

                                upto++;
                                if (upto == NumIndexTerms)
                                {
                                    break;
                                }

                                // skip terms:
                                termsDictOffsetsIter.Next();
                                for (var i = 0; i < fgtir._indexDivisor - 2; i++)
                                {
                                    termOffsetsIter.Next();
                                    termsDictOffsetsIter.Next();
                                }
                            }
                            termOffsetsM.Set(upto, termOffsetUpto);
                        }
                        finally
                        {
                            clone1.Dispose();
                            clone2.Dispose();
                            clone.Dispose();
                        }
                    }
                }
        public override void VisitDocument(int docID, StoredFieldVisitor visitor)
        {
            FieldsStream.Seek(IndexReader.GetStartPointer(docID));

            int docBase   = FieldsStream.ReadVInt();
            int chunkDocs = FieldsStream.ReadVInt();

            if (docID < docBase || docID >= docBase + chunkDocs || docBase + chunkDocs > NumDocs)
            {
                throw new CorruptIndexException("Corrupted: docID=" + docID + ", docBase=" + docBase + ", chunkDocs=" + chunkDocs + ", numDocs=" + NumDocs + " (resource=" + FieldsStream + ")");
            }

            int numStoredFields, offset, length, totalLength;

            if (chunkDocs == 1)
            {
                numStoredFields = FieldsStream.ReadVInt();
                offset          = 0;
                length          = FieldsStream.ReadVInt();
                totalLength     = length;
            }
            else
            {
                int bitsPerStoredFields = FieldsStream.ReadVInt();
                if (bitsPerStoredFields == 0)
                {
                    numStoredFields = FieldsStream.ReadVInt();
                }
                else if (bitsPerStoredFields > 31)
                {
                    throw new CorruptIndexException("bitsPerStoredFields=" + bitsPerStoredFields + " (resource=" + FieldsStream + ")");
                }
                else
                {
                    long filePointer         = FieldsStream.FilePointer;
                    PackedInts.Reader reader = PackedInts.GetDirectReaderNoHeader(FieldsStream, PackedInts.Format.PACKED, PackedIntsVersion, chunkDocs, bitsPerStoredFields);
                    numStoredFields = (int)(reader.Get(docID - docBase));
                    FieldsStream.Seek(filePointer + PackedInts.Format.PACKED.ByteCount(PackedIntsVersion, chunkDocs, bitsPerStoredFields));
                }

                int bitsPerLength = FieldsStream.ReadVInt();
                if (bitsPerLength == 0)
                {
                    length      = FieldsStream.ReadVInt();
                    offset      = (docID - docBase) * length;
                    totalLength = chunkDocs * length;
                }
                else if (bitsPerStoredFields > 31)
                {
                    throw new CorruptIndexException("bitsPerLength=" + bitsPerLength + " (resource=" + FieldsStream + ")");
                }
                else
                {
                    PackedInts.ReaderIterator it = PackedInts.GetReaderIteratorNoHeader(FieldsStream, PackedInts.Format.PACKED, PackedIntsVersion, chunkDocs, bitsPerLength, 1);
                    int off = 0;
                    for (int i = 0; i < docID - docBase; ++i)
                    {
                        off += (int)it.Next();
                    }
                    offset = off;
                    length = (int)it.Next();
                    off   += length;
                    for (int i = docID - docBase + 1; i < chunkDocs; ++i)
                    {
                        off += (int)it.Next();
                    }
                    totalLength = off;
                }
            }

            if ((length == 0) != (numStoredFields == 0))
            {
                throw new CorruptIndexException("length=" + length + ", numStoredFields=" + numStoredFields + " (resource=" + FieldsStream + ")");
            }
            if (numStoredFields == 0)
            {
                // nothing to do
                return;
            }

            DataInput documentInput;

            if (Version_Renamed >= CompressingStoredFieldsWriter.VERSION_BIG_CHUNKS && totalLength >= 2 * ChunkSize_Renamed)
            {
                Debug.Assert(ChunkSize_Renamed > 0);
                Debug.Assert(offset < ChunkSize_Renamed);

                Decompressor.Decompress(FieldsStream, ChunkSize_Renamed, offset, Math.Min(length, ChunkSize_Renamed - offset), Bytes);
                documentInput = new DataInputAnonymousInnerClassHelper(this, offset, length);
            }
            else
            {
                BytesRef bytes = totalLength <= BUFFER_REUSE_THRESHOLD ? this.Bytes : new BytesRef();
                Decompressor.Decompress(FieldsStream, totalLength, offset, length, bytes);
                Debug.Assert(bytes.Length == length);
                documentInput = new ByteArrayDataInput((byte[])(Array)bytes.Bytes, bytes.Offset, bytes.Length);
            }

            for (int fieldIDX = 0; fieldIDX < numStoredFields; fieldIDX++)
            {
                long      infoAndBits = documentInput.ReadVLong();
                int       fieldNumber = (int)((long)((ulong)infoAndBits >> CompressingStoredFieldsWriter.TYPE_BITS));
                FieldInfo fieldInfo   = FieldInfos.FieldInfo(fieldNumber);

                int bits = (int)(infoAndBits & CompressingStoredFieldsWriter.TYPE_MASK);
                Debug.Assert(bits <= CompressingStoredFieldsWriter.NUMERIC_DOUBLE, "bits=" + bits.ToString("x"));

                switch (visitor.NeedsField(fieldInfo))
                {
                case StoredFieldVisitor.Status.YES:
                    ReadField(documentInput, visitor, fieldInfo, bits);
                    break;

                case StoredFieldVisitor.Status.NO:
                    SkipField(documentInput, bits);
                    break;

                case StoredFieldVisitor.Status.STOP:
                    return;
                }
            }
        }
Ejemplo n.º 4
0
        public override Fields Get(int doc)
        {
            EnsureOpen();

            // seek to the right place
            {
                long startPointer = indexReader.GetStartPointer(doc);
                vectorsStream.Seek(startPointer);
            }

            // decode
            // - docBase: first doc ID of the chunk
            // - chunkDocs: number of docs of the chunk
            int docBase   = vectorsStream.ReadVInt();
            int chunkDocs = vectorsStream.ReadVInt();

            if (doc < docBase || doc >= docBase + chunkDocs || docBase + chunkDocs > numDocs)
            {
                throw new CorruptIndexException("docBase=" + docBase + ",chunkDocs=" + chunkDocs + ",doc=" + doc + " (resource=" + vectorsStream + ")");
            }

            int skip;        // number of fields to skip
            int numFields;   // number of fields of the document we're looking for
            int totalFields; // total number of fields of the chunk (sum for all docs)

            if (chunkDocs == 1)
            {
                skip      = 0;
                numFields = totalFields = vectorsStream.ReadVInt();
            }
            else
            {
                reader.Reset(vectorsStream, chunkDocs);
                int sum = 0;
                for (int i = docBase; i < doc; ++i)
                {
                    sum += (int)reader.Next();
                }
                skip      = sum;
                numFields = (int)reader.Next();
                sum      += numFields;
                for (int i = doc + 1; i < docBase + chunkDocs; ++i)
                {
                    sum += (int)reader.Next();
                }
                totalFields = sum;
            }

            if (numFields == 0)
            {
                // no vectors
                return(null);
            }

            // read field numbers that have term vectors
            int[] fieldNums;
            {
                int token = vectorsStream.ReadByte() & 0xFF;
                Debug.Assert(token != 0); // means no term vectors, cannot happen since we checked for numFields == 0
                int bitsPerFieldNum     = token & 0x1F;
                int totalDistinctFields = (int)((uint)token >> 5);
                if (totalDistinctFields == 0x07)
                {
                    totalDistinctFields += vectorsStream.ReadVInt();
                }
                ++totalDistinctFields;
                PackedInts.ReaderIterator it = PackedInts.GetReaderIteratorNoHeader(vectorsStream, PackedInts.Format.PACKED, packedIntsVersion, totalDistinctFields, bitsPerFieldNum, 1);
                fieldNums = new int[totalDistinctFields];
                for (int i = 0; i < totalDistinctFields; ++i)
                {
                    fieldNums[i] = (int)it.Next();
                }
            }

            // read field numbers and flags
            int[]             fieldNumOffs = new int[numFields];
            PackedInts.Reader flags;
            {
                int bitsPerOff = PackedInts.BitsRequired(fieldNums.Length - 1);
                PackedInts.Reader allFieldNumOffs = PackedInts.GetReaderNoHeader(vectorsStream, PackedInts.Format.PACKED, packedIntsVersion, totalFields, bitsPerOff);
                switch (vectorsStream.ReadVInt())
                {
                case 0:
                    PackedInts.Reader  fieldFlags = PackedInts.GetReaderNoHeader(vectorsStream, PackedInts.Format.PACKED, packedIntsVersion, fieldNums.Length, CompressingTermVectorsWriter.FLAGS_BITS);
                    PackedInts.Mutable f          = PackedInts.GetMutable(totalFields, CompressingTermVectorsWriter.FLAGS_BITS, PackedInts.COMPACT);
                    for (int i = 0; i < totalFields; ++i)
                    {
                        int fieldNumOff = (int)allFieldNumOffs.Get(i);
                        Debug.Assert(fieldNumOff >= 0 && fieldNumOff < fieldNums.Length);
                        int fgs = (int)fieldFlags.Get(fieldNumOff);
                        f.Set(i, fgs);
                    }
                    flags = f;
                    break;

                case 1:
                    flags = PackedInts.GetReaderNoHeader(vectorsStream, PackedInts.Format.PACKED, packedIntsVersion, totalFields, CompressingTermVectorsWriter.FLAGS_BITS);
                    break;

                default:
                    throw new Exception();
                }
                for (int i = 0; i < numFields; ++i)
                {
                    fieldNumOffs[i] = (int)allFieldNumOffs.Get(skip + i);
                }
            }

            // number of terms per field for all fields
            PackedInts.Reader numTerms;
            int totalTerms;
            {
                int bitsRequired = vectorsStream.ReadVInt();
                numTerms = PackedInts.GetReaderNoHeader(vectorsStream, PackedInts.Format.PACKED, packedIntsVersion, totalFields, bitsRequired);
                int sum = 0;
                for (int i = 0; i < totalFields; ++i)
                {
                    sum += (int)numTerms.Get(i);
                }
                totalTerms = sum;
            }

            // term lengths
            int docOff = 0, docLen = 0, totalLen;

            int[]   fieldLengths  = new int[numFields];
            int[][] prefixLengths = new int[numFields][];
            int[][] suffixLengths = new int[numFields][];
            {
                reader.Reset(vectorsStream, totalTerms);
                // skip
                int toSkip = 0;
                for (int i = 0; i < skip; ++i)
                {
                    toSkip += (int)numTerms.Get(i);
                }
                reader.Skip(toSkip);
                // read prefix lengths
                for (int i = 0; i < numFields; ++i)
                {
                    int   termCount          = (int)numTerms.Get(skip + i);
                    int[] fieldPrefixLengths = new int[termCount];
                    prefixLengths[i] = fieldPrefixLengths;
                    for (int j = 0; j < termCount;)
                    {
                        LongsRef next = reader.Next(termCount - j);
                        for (int k = 0; k < next.Length; ++k)
                        {
                            fieldPrefixLengths[j++] = (int)next.Longs[next.Offset + k];
                        }
                    }
                }
                reader.Skip(totalTerms - reader.Ord());

                reader.Reset(vectorsStream, totalTerms);
                // skip
                toSkip = 0;
                for (int i = 0; i < skip; ++i)
                {
                    for (int j = 0; j < numTerms.Get(i); ++j)
                    {
                        docOff += (int)reader.Next();
                    }
                }
                for (int i = 0; i < numFields; ++i)
                {
                    int   termCount          = (int)numTerms.Get(skip + i);
                    int[] fieldSuffixLengths = new int[termCount];
                    suffixLengths[i] = fieldSuffixLengths;
                    for (int j = 0; j < termCount;)
                    {
                        LongsRef next = reader.Next(termCount - j);
                        for (int k = 0; k < next.Length; ++k)
                        {
                            fieldSuffixLengths[j++] = (int)next.Longs[next.Offset + k];
                        }
                    }
                    fieldLengths[i] = Sum(suffixLengths[i]);
                    docLen         += fieldLengths[i];
                }
                totalLen = docOff + docLen;
                for (int i = skip + numFields; i < totalFields; ++i)
                {
                    for (int j = 0; j < numTerms.Get(i); ++j)
                    {
                        totalLen += (int)reader.Next();
                    }
                }
            }

            // term freqs
            int[] termFreqs = new int[totalTerms];
            {
                reader.Reset(vectorsStream, totalTerms);
                for (int i = 0; i < totalTerms;)
                {
                    LongsRef next = reader.Next(totalTerms - i);
                    for (int k = 0; k < next.Length; ++k)
                    {
                        termFreqs[i++] = 1 + (int)next.Longs[next.Offset + k];
                    }
                }
            }

            // total number of positions, offsets and payloads
            int totalPositions = 0, totalOffsets = 0, totalPayloads = 0;

            for (int i = 0, termIndex = 0; i < totalFields; ++i)
            {
                int f         = (int)flags.Get(i);
                int termCount = (int)numTerms.Get(i);
                for (int j = 0; j < termCount; ++j)
                {
                    int freq = termFreqs[termIndex++];
                    if ((f & CompressingTermVectorsWriter.POSITIONS) != 0)
                    {
                        totalPositions += freq;
                    }
                    if ((f & CompressingTermVectorsWriter.OFFSETS) != 0)
                    {
                        totalOffsets += freq;
                    }
                    if ((f & CompressingTermVectorsWriter.PAYLOADS) != 0)
                    {
                        totalPayloads += freq;
                    }
                }
                Debug.Assert(i != totalFields - 1 || termIndex == totalTerms, termIndex + " " + totalTerms);
            }

            int[][] positionIndex = PositionIndex(skip, numFields, numTerms, termFreqs);
            int[][] positions, startOffsets, lengths;
            if (totalPositions > 0)
            {
                positions = ReadPositions(skip, numFields, flags, numTerms, termFreqs, CompressingTermVectorsWriter.POSITIONS, totalPositions, positionIndex);
            }
            else
            {
                positions = new int[numFields][];
            }

            if (totalOffsets > 0)
            {
                // average number of chars per term
                float[] charsPerTerm = new float[fieldNums.Length];
                for (int i = 0; i < charsPerTerm.Length; ++i)
                {
                    charsPerTerm[i] = Number.IntBitsToFloat(vectorsStream.ReadInt());
                }
                startOffsets = ReadPositions(skip, numFields, flags, numTerms, termFreqs, CompressingTermVectorsWriter.OFFSETS, totalOffsets, positionIndex);
                lengths      = ReadPositions(skip, numFields, flags, numTerms, termFreqs, CompressingTermVectorsWriter.OFFSETS, totalOffsets, positionIndex);

                for (int i = 0; i < numFields; ++i)
                {
                    int[] fStartOffsets = startOffsets[i];
                    int[] fPositions    = positions[i];
                    // patch offsets from positions
                    if (fStartOffsets != null && fPositions != null)
                    {
                        float fieldCharsPerTerm = charsPerTerm[fieldNumOffs[i]];
                        for (int j = 0; j < startOffsets[i].Length; ++j)
                        {
                            fStartOffsets[j] += (int)(fieldCharsPerTerm * fPositions[j]);
                        }
                    }
                    if (fStartOffsets != null)
                    {
                        int[] fPrefixLengths = prefixLengths[i];
                        int[] fSuffixLengths = suffixLengths[i];
                        int[] fLengths       = lengths[i];
                        for (int j = 0, end = (int)numTerms.Get(skip + i); j < end; ++j)
                        {
                            // delta-decode start offsets and  patch lengths using term lengths
                            int termLength = fPrefixLengths[j] + fSuffixLengths[j];
                            lengths[i][positionIndex[i][j]] += termLength;
                            for (int k = positionIndex[i][j] + 1; k < positionIndex[i][j + 1]; ++k)
                            {
                                fStartOffsets[k] += fStartOffsets[k - 1];
                                fLengths[k]      += termLength;
                            }
                        }
                    }
                }
            }
            else
            {
                startOffsets = lengths = new int[numFields][];
            }
            if (totalPositions > 0)
            {
                // delta-decode positions
                for (int i = 0; i < numFields; ++i)
                {
                    int[] fPositions     = positions[i];
                    int[] fpositionIndex = positionIndex[i];
                    if (fPositions != null)
                    {
                        for (int j = 0, end = (int)numTerms.Get(skip + i); j < end; ++j)
                        {
                            // delta-decode start offsets
                            for (int k = fpositionIndex[j] + 1; k < fpositionIndex[j + 1]; ++k)
                            {
                                fPositions[k] += fPositions[k - 1];
                            }
                        }
                    }
                }
            }

            // payload lengths
            int[][] payloadIndex       = new int[numFields][];
            int     totalPayloadLength = 0;
            int     payloadOff         = 0;
            int     payloadLen         = 0;

            if (totalPayloads > 0)
            {
                reader.Reset(vectorsStream, totalPayloads);
                // skip
                int termIndex = 0;
                for (int i = 0; i < skip; ++i)
                {
                    int f         = (int)flags.Get(i);
                    int termCount = (int)numTerms.Get(i);
                    if ((f & CompressingTermVectorsWriter.PAYLOADS) != 0)
                    {
                        for (int j = 0; j < termCount; ++j)
                        {
                            int freq = termFreqs[termIndex + j];
                            for (int k = 0; k < freq; ++k)
                            {
                                int l = (int)reader.Next();
                                payloadOff += l;
                            }
                        }
                    }
                    termIndex += termCount;
                }
                totalPayloadLength = payloadOff;
                // read doc payload lengths
                for (int i = 0; i < numFields; ++i)
                {
                    int f         = (int)flags.Get(skip + i);
                    int termCount = (int)numTerms.Get(skip + i);
                    if ((f & CompressingTermVectorsWriter.PAYLOADS) != 0)
                    {
                        int totalFreq = positionIndex[i][termCount];
                        payloadIndex[i] = new int[totalFreq + 1];
                        int posIdx = 0;
                        payloadIndex[i][posIdx] = payloadLen;
                        for (int j = 0; j < termCount; ++j)
                        {
                            int freq = termFreqs[termIndex + j];
                            for (int k = 0; k < freq; ++k)
                            {
                                int payloadLength = (int)reader.Next();
                                payloadLen += payloadLength;
                                payloadIndex[i][posIdx + 1] = payloadLen;
                                ++posIdx;
                            }
                        }
                        Debug.Assert(posIdx == totalFreq);
                    }
                    termIndex += termCount;
                }
                totalPayloadLength += payloadLen;
                for (int i = skip + numFields; i < totalFields; ++i)
                {
                    int f         = (int)flags.Get(i);
                    int termCount = (int)numTerms.Get(i);
                    if ((f & CompressingTermVectorsWriter.PAYLOADS) != 0)
                    {
                        for (int j = 0; j < termCount; ++j)
                        {
                            int freq = termFreqs[termIndex + j];
                            for (int k = 0; k < freq; ++k)
                            {
                                totalPayloadLength += (int)reader.Next();
                            }
                        }
                    }
                    termIndex += termCount;
                }
                Debug.Assert(termIndex == totalTerms, termIndex + " " + totalTerms);
            }

            // decompress data
            BytesRef suffixBytes = new BytesRef();

            decompressor.Decompress(vectorsStream, totalLen + totalPayloadLength, docOff + payloadOff, docLen + payloadLen, suffixBytes);
            suffixBytes.Length = docLen;
            BytesRef payloadBytes = new BytesRef(suffixBytes.Bytes, suffixBytes.Offset + docLen, payloadLen);

            int[] FieldFlags = new int[numFields];
            for (int i = 0; i < numFields; ++i)
            {
                FieldFlags[i] = (int)flags.Get(skip + i);
            }

            int[] fieldNumTerms = new int[numFields];
            for (int i = 0; i < numFields; ++i)
            {
                fieldNumTerms[i] = (int)numTerms.Get(skip + i);
            }

            int[][] fieldTermFreqs = new int[numFields][];
            {
                int termIdx = 0;
                for (int i = 0; i < skip; ++i)
                {
                    termIdx += (int)numTerms.Get(i);
                }
                for (int i = 0; i < numFields; ++i)
                {
                    int termCount = (int)numTerms.Get(skip + i);
                    fieldTermFreqs[i] = new int[termCount];
                    for (int j = 0; j < termCount; ++j)
                    {
                        fieldTermFreqs[i][j] = termFreqs[termIdx++];
                    }
                }
            }

            Debug.Assert(Sum(fieldLengths) == docLen, Sum(fieldLengths) + " != " + docLen);

            return(new TVFields(this, fieldNums, FieldFlags, fieldNumOffs, fieldNumTerms, fieldLengths, prefixLengths, suffixLengths, fieldTermFreqs, positionIndex, positions, startOffsets, lengths, payloadBytes, payloadIndex, suffixBytes));
        }