Golang store.IndexInput類代碼示例

func (r *BlockTreeTermsReader) readIndexHeader(input store.IndexInput) (version int, err error) {
	version, err = asInt(codec.CheckHeader(input, BTT_INDEX_CODEC_NAME, BTT_INDEX_VERSION_START, BTT_INDEX_VERSION_CURRENT))
	if err != nil {
		return version, err
	}
	if version < BTT_INDEX_VERSION_APPEND_ONLY {
		r.indexDirOffset, err = input.ReadLong()
		if err != nil {
			return version, err
		}
	}
	return version, nil
}

func (r *Lucene41PostingsReader) Init(termsIn store.IndexInput) error {
	log.Printf("Initializing from: %v", termsIn)
	// Make sure we are talking to the matching postings writer
	_, err := codec.CheckHeader(termsIn, LUCENE41_TERMS_CODEC, LUCENE41_VERSION_START, LUCENE41_VERSION_CURRENT)
	if err != nil {
		return err
	}
	indexBlockSize, err := termsIn.ReadVInt()
	if err != nil {
		return err
	}
	log.Printf("Index block size: %v", indexBlockSize)
	if indexBlockSize != LUCENE41_BLOCK_SIZE {
		panic(fmt.Sprintf("index-time BLOCK_SIZE (%v) != read-time BLOCK_SIZE (%v)", indexBlockSize, LUCENE41_BLOCK_SIZE))
	}
	return nil
}

func (r *BlockTreeTermsReader) seekDir(input store.IndexInput, dirOffset int64) (err error) {
	log.Printf("Seeking to: %v", dirOffset)
	if r.version >= BTT_INDEX_VERSION_APPEND_ONLY {
		input.Seek(input.Length() - 8)
		if dirOffset, err = input.ReadLong(); err != nil {
			return err
		}
	}
	input.Seek(dirOffset)
	return nil
}

func newFieldReader(owner *BlockTreeTermsReader,
	fieldInfo FieldInfo, numTerms int64, rootCode []byte,
	sumTotalTermFreq, sumDocFreq int64, docCount int32, indexStartFP int64,
	indexIn store.IndexInput) (r FieldReader, err error) {
	log.Print("Initializing FieldReader...")
	if numTerms <= 0 {
		panic("assert fail")
	}
	// assert numTerms > 0
	r = FieldReader{
		BlockTreeTermsReader: owner,
		fieldInfo:            fieldInfo,
		numTerms:             numTerms,
		sumTotalTermFreq:     sumTotalTermFreq,
		sumDocFreq:           sumDocFreq,
		docCount:             docCount,
		indexStartFP:         indexStartFP,
		rootCode:             rootCode,
	}
	log.Printf("BTTR: seg=%v field=%v rootBlockCode=%v divisor=",
		owner.segment, fieldInfo.name, rootCode)

	in := store.NewByteArrayDataInput(rootCode)
	n, err := in.ReadVLong()
	if err != nil {
		return r, err
	}
	r.rootBlockFP = int64(uint64(n) >> BTT_OUTPUT_FLAGS_NUM_BITS)

	if indexIn != nil {
		clone := indexIn.Clone()
		log.Printf("start=%v field=%v", indexStartFP, fieldInfo.name)
		clone.Seek(indexStartFP)
		r.index, err = util.LoadFST(clone, util.ByteSequenceOutputsSingleton())
	}

	return r, err
}

/* Reads but does not decode the byte[] blob holding
   metadata for the current terms block */
func (r *Lucene41PostingsReader) ReadTermsBlock(termsIn store.IndexInput, fieldInfo FieldInfo, _termState *BlockTermState) (err error) {
	termState := _termState.Self.(*intBlockTermState)
	numBytes, err := asInt(termsIn.ReadVInt())
	if err != nil {
		return err
	}

	if termState.bytes == nil {
		// TODO over-allocate
		termState.bytes = make([]byte, numBytes)
		termState.bytesReader = store.NewEmptyByteArrayDataInput()
	} else if len(termState.bytes) < numBytes {
		// TODO over-allocate
		termState.bytes = make([]byte, numBytes)
	}

	err = termsIn.ReadBytes(termState.bytes)
	if err != nil {
		return err
	}
	termState.bytesReader.Reset(termState.bytes)
	return nil
}

func newCompressingStoredFieldsIndexReader(fieldsIndexIn store.IndexInput, si SegmentInfo) (r *CompressingStoredFieldsIndexReader, err error) {
	r = &CompressingStoredFieldsIndexReader{}
	r.maxDoc = int(si.docCount)
	r.docBases = make([]int, 0, 16)
	r.startPointers = make([]int64, 0, 16)
	r.avgChunkDocs = make([]int, 0, 16)
	r.avgChunkSizes = make([]int64, 0, 16)
	r.docBasesDeltas = make([]util.PackedIntsReader, 0, 16)
	r.startPointersDeltas = make([]util.PackedIntsReader, 0, 16)

	packedIntsVersion, err := fieldsIndexIn.ReadVInt()
	if err != nil {
		return nil, err
	}

	for blockCount := 0; ; blockCount++ {
		numChunks, err := fieldsIndexIn.ReadVInt()
		if err != nil {
			return nil, err
		}
		if numChunks == 0 {
			break
		}

		{ // doc bases
			n, err := fieldsIndexIn.ReadVInt()
			if err != nil {
				return nil, err
			}
			r.docBases = append(r.docBases, int(n))
			n, err = fieldsIndexIn.ReadVInt()
			if err != nil {
				return nil, err
			}
			r.avgChunkDocs = append(r.avgChunkDocs, int(n))
			bitsPerDocBase, err := fieldsIndexIn.ReadVInt()
			if err != nil {
				return nil, err
			}
			if bitsPerDocBase > 32 {
				return nil, errors.New(fmt.Sprintf("Corrupted bitsPerDocBase (resource=%v)", fieldsIndexIn))
			}
			pr, err := util.NewPackedReaderNoHeader(fieldsIndexIn, util.PACKED, packedIntsVersion, numChunks, uint32(bitsPerDocBase))
			if err != nil {
				return nil, err
			}
			r.docBasesDeltas = append(r.docBasesDeltas, pr)
		}

		{ // start pointers
			n, err := fieldsIndexIn.ReadVLong()
			if err != nil {
				return nil, err
			}
			r.startPointers = append(r.startPointers, n)
			n, err = fieldsIndexIn.ReadVLong()
			if err != nil {
				return nil, err
			}
			r.avgChunkSizes = append(r.avgChunkSizes, n)
			bitsPerStartPointer, err := fieldsIndexIn.ReadVInt()
			if err != nil {
				return nil, err
			}
			if bitsPerStartPointer > 64 {
				return nil, errors.New(fmt.Sprintf("Corrupted bitsPerStartPonter (resource=%v)", fieldsIndexIn))
			}
			pr, err := util.NewPackedReaderNoHeader(fieldsIndexIn, util.PACKED, packedIntsVersion, numChunks, uint32(bitsPerStartPointer))
			if err != nil {
				return nil, err
			}
			r.startPointersDeltas = append(r.startPointersDeltas, pr)
		}
	}

	return r, nil
}

// CompressingStoredFieldsReader.java L90
func newCompressingStoredFieldsReader(d store.Directory, si SegmentInfo, segmentSuffix string, fn FieldInfos,
	ctx store.IOContext, formatName string, compressionMode codec.CompressionMode) (r *CompressingStoredFieldsReader, err error) {
	r = &CompressingStoredFieldsReader{}
	r.compressionMode = compressionMode
	segment := si.name
	r.fieldInfos = fn
	r.numDocs = int(si.docCount)

	var indexStream store.IndexInput
	success := false
	defer func() {
		if !success {
			log.Println("Failed to initialize CompressionStoredFieldsReader.")
			if err != nil {
				log.Print(err)
			}
			util.Close(r, indexStream)
		}
	}()

	// Load the index into memory
	indexStreamFN := util.SegmentFileName(segment, segmentSuffix, LUCENE40_SF_FIELDS_INDEX_EXTENSION)
	indexStream, err = d.OpenInput(indexStreamFN, ctx)
	if err != nil {
		return nil, err
	}
	codecNameIdx := formatName + CODEC_SFX_IDX
	codec.CheckHeader(indexStream, codecNameIdx, CODEC_SFX_VERSION_START, CODEC_SFX_VERSION_CURRENT)
	if int64(codec.HeaderLength(codecNameIdx)) != indexStream.FilePointer() {
		panic("assert fail")
	}
	r.indexReader, err = newCompressingStoredFieldsIndexReader(indexStream, si)
	if err != nil {
		return nil, err
	}
	err = indexStream.Close()
	if err != nil {
		return nil, err
	}
	indexStream = nil

	// Open the data file and read metadata
	fieldsStreamFN := util.SegmentFileName(segment, segmentSuffix, LUCENE40_SF_FIELDS_EXTENSION)
	r.fieldsStream, err = d.OpenInput(fieldsStreamFN, ctx)
	if err != nil {
		return nil, err
	}
	codecNameDat := formatName + CODEC_SFX_DAT
	codec.CheckHeader(r.fieldsStream, codecNameDat, CODEC_SFX_VERSION_START, CODEC_SFX_VERSION_CURRENT)
	if int64(codec.HeaderLength(codecNameDat)) != r.fieldsStream.FilePointer() {
		panic("assert fail")
	}

	n, err := r.fieldsStream.ReadVInt()
	if err != nil {
		return nil, err
	}
	r.packedIntsVersion = int(n)
	r.decompressor = compressionMode.NewDecompressor()
	r.bytes = make([]byte, 0)

	success = true
	return r, nil
}

func newBlockTreeTermsReader(dir store.Directory, fieldInfos FieldInfos, info SegmentInfo,
	postingsReader PostingsReaderBase, ctx store.IOContext,
	segmentSuffix string, indexDivisor int) (p FieldsProducer, err error) {
	log.Print("Initializing BlockTreeTermsReader...")
	fp := &BlockTreeTermsReader{
		postingsReader: postingsReader,
		fields:         make(map[string]FieldReader),
		segment:        info.name,
	}
	fp.in, err = dir.OpenInput(util.SegmentFileName(info.name, segmentSuffix, BTT_EXTENSION), ctx)
	if err != nil {
		return fp, err
	}

	success := false
	var indexIn store.IndexInput
	defer func() {
		if !success {
			log.Print("Failed to initialize BlockTreeTermsReader.")
			if err != nil {
				log.Print("DEBUG ", err)
			}
			// this.close() will close in:
			util.CloseWhileSuppressingError(indexIn, fp)
		}
	}()

	fp.version, err = fp.readHeader(fp.in)
	if err != nil {
		return fp, err
	}
	log.Printf("Version: %v", fp.version)

	if indexDivisor != -1 {
		indexIn, err = dir.OpenInput(util.SegmentFileName(info.name, segmentSuffix, BTT_INDEX_EXTENSION), ctx)
		if err != nil {
			return fp, err
		}

		indexVersion, err := fp.readIndexHeader(indexIn)
		if err != nil {
			return fp, err
		}
		log.Printf("Index version: %v", indexVersion)
		if int(indexVersion) != fp.version {
			return fp, errors.New(fmt.Sprintf("mixmatched version files: %v=%v,%v=%v", fp.in, fp.version, indexIn, indexVersion))
		}
	}

	// Have PostingsReader init itself
	postingsReader.Init(fp.in)

	// Read per-field details
	fp.seekDir(fp.in, fp.dirOffset)
	if indexDivisor != -1 {
		fp.seekDir(indexIn, fp.indexDirOffset)
	}

	numFields, err := fp.in.ReadVInt()
	if err != nil {
		return fp, err
	}
	log.Printf("Fields number: %v", numFields)
	if numFields < 0 {
		return fp, errors.New(fmt.Sprintf("invalid numFields: %v (resource=%v)", numFields, fp.in))
	}

	for i := int32(0); i < numFields; i++ {
		log.Printf("Next field...")
		field, err := fp.in.ReadVInt()
		if err != nil {
			return fp, err
		}
		log.Printf("Field: %v", field)

		numTerms, err := fp.in.ReadVLong()
		if err != nil {
			return fp, err
		}
		// assert numTerms >= 0
		log.Printf("Terms number: %v", numTerms)

		numBytes, err := fp.in.ReadVInt()
		if err != nil {
			return fp, err
		}
		log.Printf("Bytes number: %v", numBytes)

		rootCode := make([]byte, numBytes)
		err = fp.in.ReadBytes(rootCode)
		if err != nil {
			return fp, err
		}
		fieldInfo := fieldInfos.byNumber[field]
		// assert fieldInfo != nil
		var sumTotalTermFreq int64
		if fieldInfo.indexOptions == INDEX_OPT_DOCS_ONLY {
			sumTotalTermFreq = -1
		} else {
			sumTotalTermFreq, err = fp.in.ReadVLong()
//.........這裏部分代碼省略.........

/*
Lucene42DocValuesProducer.java
Line 126
*/
func (dvp *Lucene42DocValuesProducer) readFields(meta store.IndexInput, infos FieldInfos) (err error) {
	fieldNumber, err := meta.ReadVInt()
	for fieldNumber != -1 && err == nil {
		fieldType, err := meta.ReadByte()
		if err != nil {
			break
		}
		switch fieldType {
		case LUCENE42_DV_NUMBER:
			entry := NumericEntry{}
			entry.offset, err = meta.ReadLong()
			if err != nil {
				return err
			}
			entry.format, err = meta.ReadByte()
			if err != nil {
				return err
			}
			switch entry.format {
			case LUCENE42_DV_DELTA_COMPRESSED:
			case LUCENE42_DV_TABLE_COMPRESSED:
			case LUCENE42_DV_GCD_COMPRESSED:
			case LUCENE42_DV_UNCOMPRESSED:
			default:
				return errors.New(fmt.Sprintf("Unknown format: %v, input=%v", entry.format, meta))
			}
			if entry.format != LUCENE42_DV_UNCOMPRESSED {
				n, err := meta.ReadVInt()
				if err != nil {
					return err
				}
				entry.packedIntsVersion = int(n)
			}
		case LUCENE42_DV_BYTES:
			panic("not implemented yet")
		case LUCENE42_DV_FST:
			panic("not implemented yet")
		default:
			return errors.New(fmt.Sprintf("invalid entry type: %v, input=%v", fieldType, meta))
		}
		fieldNumber, err = meta.ReadVInt()
	}
	return err
}