util

package
v0.0.0-...-d0be9ee Latest Latest
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 Go to latest Published: Dec 10, 2015 License: Apache-2.0 Imports: 15 Imported by: 54

Documentation

Index

Constants

View Source 
const (
	BYTE_BLOCK_SHIFT = 15
	BYTE_BLOCK_SIZE  = 1 << BYTE_BLOCK_SHIFT
	BYTE_BLOCK_MASK  = BYTE_BLOCK_SIZE - 1
)
View Source 
const (
	NUM_BYTES_CHAR  = 2 // UTF8 uses 1-4 bytes to represent each rune
	NUM_BYTES_SHORT = 2
	NUM_BYTES_INT   = 8
	NUM_BYTES_FLOAT = 4
	NUM_BYTES_LONG  = 8

	/* Number of bytes to represent an object reference */
	NUM_BYTES_OBJECT_REF = 8

	// Number of bytes to represent an object header (no fields, no alignments).
	NUM_BYTES_OBJECT_HEADER = 16

	// Number of bytes to represent an array header (no content, but with alignments).
	NUM_BYTES_ARRAY_HEADER = 24

	// A constant specifying the object alignment boundary inside the
	// JVM. Objects will always take a full multiple of this constant,
	// possibly wasting some space.
	NUM_BYTES_OBJECT_ALIGNMENT = 8
)

amd64 system

View Source 
const (
	MINRUN        = 32
	RUN_THRESHOLD = 64
	STACKSIZE     = 40 // depends on MINRUN
	MIN_GALLOP    = 7
)
View Source 
const (
	UNI_SUR_HIGH_START = 0xD800
	UNI_SUR_HIGH_END   = 0xDBFF
	UNI_SUR_LOW_START  = 0xDC00
	UNI_SUR_LOW_END    = 0xDFFF
)
View Source 
const DATA_OUTPUT_COPY_BUFFER_SIZE = 16384
View Source 
const FORMAT = "2006/01/02 15:04:05"
View Source 
const INT_BLOCK_MASK = INT_BLOCK_SIZE - 1
View Source 
const INT_BLOCK_SHIFT = 13
View Source 
const INT_BLOCK_SIZE = 1 << INT_BLOCK_SHIFT
View Source 
const MAX_ARRAY_LENGTH = math.MaxInt32 - NUM_BYTES_ARRAY_HEADER

Maximum length for an array

View Source 
const (
	// The default precision step used by LongField, DoubleField,
	// NumericTokenStream, NumericRangeQuery, and NumericRangeFilter.
	NUMERIC_PRECISION_STEP_DEFAULT = 16
)
View Source 
const (
	SEGMENTS = "segments"
)
View Source 
const SKIP_BUFFER_SIZE = 1024
View Source 
const SORTER_THRESHOLD = 20

Variables

View Source 
var (
	// Match settings and bugs in Lucene's 3.1 release.
	VERSION_31 = Version([4]int{3, 1, 0, 0})
	// Match settings and bugs in Lucene's 4.0 release.
	VERSION_4_0 = Version([4]int{4, 0, 0, 0})
	// Match settings and bugs in Lucene's 4.5 release.
	VERSION_45 = Version([4]int{4, 5, 0, 0})
	// Match settings and bugs in Lucene's 4.9 release.
	// Use this to get the latest and greatest settings, bug fixes, etc,
	// for Lucnee.
	VERSION_49     = Version([4]int{4, 9, 0, 0})
	VERSION_4_10   = Version([4]int{4, 10, 0, 0})
	VERSION_4_10_1 = Version([4]int{4, 10, 1, 0})

	VERSION_LATEST = VERSION_4_10_1
)
View Source 
var BIT_LISTS = []int{}/* 256 elements not displayed */

The General Idea: instead of having an array per byte that has the offsets of the next set bit, that array could be packed inside a 32 bit integer (8 4 bit numbers). That should be faster than accessing an array for each index, and the total array size is kept smaller (256*sizeof(int))=1K **** the python code that generated bitlist 

def bits2int(val):
arr=0
for shift in range(8,0,-1):
  if val & 0x80:
    arr = (arr << 4) | shift
  val = val << 1
return arr

def int_table():
  tbl = [ hex(bits2int(val)).strip('L') for val in range(256) ]
  return ','.join(tbl)
*****
View Source 
var BYTE_COUNTS = []int{}/* 256 elements not displayed */
View Source 
var CODEC_FILE_PATTERN = regexp.MustCompile("_[a-z0-9]+(_.*)?\\..*")

All files created by codecs must match this pattern (checked in SegmentInfo)

View Source 
var EMPTY_BYTES = []byte{}

An empty byte slice for convenience

View Source 
var EMPTY_BYTES_REF_ITERATOR = &emptyBytesRefIterator{}
View Source 
var EMPTY_INTS = []int{}

An empty integer array for convenience

View Source 
var FIRST_LEVEL_SIZE = LEVEL_SIZE_ARRAY[0]

THe first level size for new slices

View Source 
var GOOD_FAST_HASH_SEED = func() uint32 {
	if prop := os.Getenv("tests_seed"); prop != "" {

		if len(prop) > 8 {
			prop = prop[len(prop)-8:]
		}
		n, err := strconv.ParseInt(prop, 16, 64)
		if err != nil {
			panic(err)
		}
		fmt.Printf("tests_seed=%v\n", uint32(n))
		return uint32(n)
	} else {
		return uint32(time.Now().Nanosecond())
	}
}()

Poached from Guava: set a different salt/seed for each VM instance, to frustrate hash key collision denial of service attacks, and to catch any places that somehow rely on hash function/order across VM instances:

View Source 
var LEVEL_SIZE_ARRAY = []int{5, 14, 20, 30, 40, 40, 80, 80, 120, 200}

An array holding the level sizes for byte slices.

View Source 
var LUCENE_MAIN_VERSION = VERSION_LATEST.String()

This is the internal Lucene version, recorded into each segment.

View Source 
var LUCENE_VERSION = VERSION_LATEST.String()

This is the Lucene version for display purpose.

View Source 
var MESSAGE_ID int32 // atomic
View Source 
var NEXT_LEVEL_ARRAY = []int{1, 2, 3, 4, 5, 6, 7, 8, 9, 9}

An array holding the offset into the LEVEL_SIZE_ARRAY to quickly navigate to the next slice level.

View Source 
var NO_OUTPUT = NoOutput(true)

Instance of InfoStream that does no logging at all.

Functions

func AlignObjectSize 

func AlignObjectSize(size int64) int64

Aligns an object size to be the next multiple of NUM_BYTES_OBJECT_ALIGNMENT

func BitCount 

func BitCount(b byte) int

Return the number of bits sets in b.

func Byte315ToFloat 

func Byte315ToFloat(b byte) float32

* byteToFloat(b, mantissaBits=3, zeroExponent=15)

func Close 

func Close(objects ...io.Closer) error

func CloseWhileHandlingError 

func CloseWhileHandlingError(priorErr error, objects ...io.Closer) error

func CloseWhileSuppressingError 

func CloseWhileSuppressingError(objects ...io.Closer)

func DeleteFilesIgnoringErrors 

func DeleteFilesIgnoringErrors(dir FileDeleter, files ...string)

Deletes all given files, suppressing all throw errors.

Note that the files should not be nil.

func FileNameFromGeneration 

func FileNameFromGeneration(base, ext string, gen int64) string

func FloatToByte315 

func FloatToByte315(f float32) int8

floatToByte(b, mantissaBits=3, zeroExponent=15) smallest non-zero value = 5.820766E-10 largest value = 7.5161928E9 epsilon = 0.125

func Fsync 

func Fsync(fileToSync string, isDir bool) error

Ensure that any writes to the given file is written to the storage device that contains it.

func Gcd 

func Gcd(a, b int64) int64

Return the greatest common divisor of a and b, consistently with big.GCD(a, b).

NOTE: A greatest common divisor must be positive, but 2^64 cannot be expressed as an int64 although it is the GCD of math.MinInt64 and 0 and the GCD of math.MinInt64 and math.MinInt64. So in these 2 cases, and only them, this method will return math.MinInt64.

func GrowByteSlice 

func GrowByteSlice(arr []byte, minSize int) []byte

L343

func GrowIntSlice 

func GrowIntSlice(arr []int, minSize int) []int

L285

func Hashstr 

func Hashstr(sep string) int

simple string hash used by Go strings package

func IntroSort 

func IntroSort(data sort.Interface)

func IsValidUTF16String 

func IsValidUTF16String(s []rune) bool

L345

func ItoHex 

func ItoHex(i int64) string

func Log 

func Log(x int64, base int) int

Returns x <= 0 ? 0 : floor(log(x) ? log(base))

func MurmurHash3_x86_32 

func MurmurHash3_x86_32(data []byte, seed uint32) uint32

Returns the MurmurHash3_x86_32 hash. Original source/tests at https://github.com/yonik/java_util/

func NumberOfTrailingZeros 

func NumberOfTrailingZeros(n int64) uint

func Oversize 

func Oversize(minTargetSize int, bytesPerElement int) int

L152 * Returns an array size >= minTargetSize, generally

  • over-allocating exponentially to achieve amortized
  • linear-time cost as the array grows. *
  • NOTE: this was originally borrowed from Python 2.4.2
  • listobject.c sources (attribution in LICENSE.txt), but
  • has now been substantially changed based on
  • discussions from java-dev thread with subject "Dynamic
  • array reallocation algorithms", started on Jan 12
  • 2010. *
  • @param minTargetSize Minimum required value to be returned.
  • @param bytesPerElement Bytes used by each element of
  • the array. See constants in {@link RamUsageEstimator}. *
  • @lucene.internal

func ParseGeneration 

func ParseGeneration(filename string) int64

Returns the generation from this file name, or 0 if there is no generation.

func ParseSegmentName 

func ParseSegmentName(filename string) string

func SegmentFileName 

func SegmentFileName(name, suffix, ext string) string

func SetDefaultInfoStream 

func SetDefaultInfoStream(infoStream InfoStream)

Sets the default InfoStream used by a newly instantiated classes. It cannot be nil, to disable logging use NO_OUTPUT.

func ShallowSizeOf 

func ShallowSizeOf(obj interface{}) int64

Estimates a "shallow" memory usage of the given object. For slices, this will be the memory taken by slice storage (no subreferences will be followed). For objects, this will be the memory taken by the fields.

func ShallowSizeOfInstance 

func ShallowSizeOfInstance(clazz reflect.Type) int64

func SizeOf 

func SizeOf(arr interface{}) int64

Returns the size in bytes of the object.

func StartsWith 

func StartsWith(ref, prefix []byte) bool

Returns true iff the ref starts with the given prefix. Otherwise false.

func StripExtension 

func StripExtension(filename string) string

func StripSegmentName 

func StripSegmentName(filename string) string

func TimSort 

func TimSort(data sort.Interface)

L699

Sorts the given array slice in its own order. This method uses the Tim sort algorithm, but falls back to binary sort for small arrays.

func UTF8SortedAsUnicodeLess 

func UTF8SortedAsUnicodeLess(aBytes, bBytes []byte) bool

func ZigZagDecodeLong 

func ZigZagDecodeLong(l int64) int64

func ZigZagEncodeLong 

func ZigZagEncodeLong(l int64) int64

Types

type Accountable 

type Accountable interface {
	// Return the memory usage of this object in bytes. Negative values are illegal.
	RamBytesUsed() int64
}

An object whose RAM usage can be computed.

type ArrayTimSorter 

type ArrayTimSorter struct {
	*TimSorter
	// contains filtered or unexported fields
}

A TimSorter for object arrays

type Attribute 

type Attribute interface {
}

Base interface for attributes.

type AttributeFactory 

type AttributeFactory interface {
	Create(string) AttributeImpl
}

An AttributeFactory creates instances of AttributeImpls.

type AttributeImpl 

type AttributeImpl interface {
	Interfaces() []string
	Clone() AttributeImpl
	// Clears the values in this AttributeImpl and resets it to its
	// default value. If this implementation implements more than one
	// Attribute interface, it clears all.
	Clear()
	CopyTo(target AttributeImpl)
}

Base class for Attributes that can be added to a AttributeSource.

Attributes are used to add data in a dynamic, yet type-safe way to a source of usually streamed ojects, e.g. a TokenStream.

type AttributeSource 

type AttributeSource struct {
	// contains filtered or unexported fields
}

An AttributeSource contains a list of different AttributeImpls, and methods to add and get them. There can only be a single instance of an attribute in the same AttributeSource instance. This is ensured by passing in the actual type of the Attribute (reflect.TypeOf(Attribute)) to the #AddAttribute(Type), which then checks if an instance of that type is already present. If yes, it returns the instance, otherwise it creates a new instance and returns it.

func NewAttributeSourceFrom 

func NewAttributeSourceFrom(input *AttributeSource) *AttributeSource

An AttributeSource that uses the same attributes as the supplied one.

func NewAttributeSourceWith 

func NewAttributeSourceWith(factory AttributeFactory) *AttributeSource

An AttributeSource using the supplied AttributeFactory for creating new Attribute instance.

func (*AttributeSource) Add 

func (as *AttributeSource) Add(s string) Attribute

The caller must pass in a Attribute instance. This method first checks if an instance of that type is already in this AttributeSource and returns it. Otherwise a new instance is created, added to this AttributeSource and returned.

func (*AttributeSource) AddImpl 

func (as *AttributeSource) AddImpl(att AttributeImpl)

Expert: Adds a custom AttributeImpl instance with one or more Attribute interfaces.

Please note: it is not guaranteed, that att is added to the AttributeSource, because the provided attributes may already exist. You should always retrieve the wanted attributes using Get() after adding with this method and cast to you class.

The recommended way to use custom implementations is using an AttributeFactory.

func (*AttributeSource) CaptureState 

func (as *AttributeSource) CaptureState() (state *AttributeState)

func (*AttributeSource) Clear 

func (as *AttributeSource) Clear()

Resets all Attributes in this AttributeSource by calling AttributeImpl.clear() on each Attribute implementation.

func (*AttributeSource) Get 

func (as *AttributeSource) Get(s string) Attribute

Returns the instance of the passe in Attribute contained in this AttributeSource

func (*AttributeSource) Has 

func (as *AttributeSource) Has(s string) bool

Returns true, iff this AttributeSource contains the passed-in Attribute.

func (*AttributeSource) RestoreState 

func (as *AttributeSource) RestoreState(state *AttributeState)

func (*AttributeSource) String 

func (as *AttributeSource) String() string

Returns a string consisting of the class's simple name, the hex representation of the identity hash code, and the current reflection of all attributes.

type AttributeState 

type AttributeState struct {
	// contains filtered or unexported fields
}

This class holds the state of an AttributeSource

func (*AttributeState) Clone 

func (s *AttributeState) Clone() *AttributeState

type Bits 

type Bits interface {
	/**
	 * Returns the value of the bit with the specified <code>index</code>.
	 * @param index index, should be non-negative and &lt; {@link #length()}.
	 *        The result of passing negative or out of bounds values is undefined
	 *        by this interface, <b>just don't do it!</b>
	 * @return <code>true</code> if the bit is set, <code>false</code> otherwise.
	 */
	At(index int) bool

	// Returns the number of bits in the set
	Length() int
}

*

  • Interface for Bitset-like structures.
  • @lucene.experimental

type ByteAllocator 

type ByteAllocator interface {
	// contains filtered or unexported methods
}

Abstract class for allocating and freeing byte blocks.

type ByteAllocatorImpl 

type ByteAllocatorImpl struct {
	// contains filtered or unexported fields
}

type ByteBlockPool 

type ByteBlockPool struct {
	Buffers [][]byte

	ByteUpto   int
	Buffer     []byte
	ByteOffset int
	// contains filtered or unexported fields
}

Class that Posting and PostingVector use to writ ebyte streams into shared fixed-size []byte arrays. The idea is to allocate slices of increasing lengths. For example, the first slice is 5 bytes, the next slice is 14, etc. We start by writing out bytes into the first 5 bytes. When we hit the end of the slice, we allocate the next slice and then write the address of the next slice into the last 4 bytes of the previous slice (the "forwarding address").

Each slice is filled with 0's initially, and we mark the end with a non-zero byte. This way the methods that are writing into the slice don't need to record its length and instead allocate a new slice once they hit a non-zero byte.

func NewByteBlockPool 

func NewByteBlockPool(allocator ByteAllocator) *ByteBlockPool

func (*ByteBlockPool) AllocSlice 

func (p *ByteBlockPool) AllocSlice(slice []byte, upto int) int

Creates a new byte slice with the given starting size and returns the slices offset in the pool.

func (*ByteBlockPool) NewSlice 

func (pool *ByteBlockPool) NewSlice(size int) int

Allocates a new slice with the given size.

func (*ByteBlockPool) NextBuffer 

func (pool *ByteBlockPool) NextBuffer()

Advances the pool to its next buffer. This method should be called once after the constructor to initialize the pool. In contrast to the constructor, a ByteBlockPool.Reset() call will advance the pool to its first buffer immediately.

func (*ByteBlockPool) Reset 

func (pool *ByteBlockPool) Reset(zeroFillBuffers, reuseFirst bool)

Expert: Resets the pool to its initial state reusing the first buffer.

func (*ByteBlockPool) SetBytesRef 

func (p *ByteBlockPool) SetBytesRef(term *BytesRef, textStart int)

Fill in a BytesRef from term's length & bytes encoded in byte block

type BytesRef 

type BytesRef struct {
	// The contents of the BytesRef.
	Bytes  []byte
	Offset int
	Length int
}

Represents []byte, as a slice (offset + length) into an existing []byte, similar to Go's byte slice.

Important note: Unless otherwise noted, GoLucene uses []byte directly to represent terms that are encoded as UTF8 bytes in the index. It uses this class in cases when caller needs to hold a reference, while allowing underlying []byte to change.

func DeepCopyOf 

func DeepCopyOf(other *BytesRef) *BytesRef

Creates a new BytesRef that points to a copy of the bytes from other.

The returned BytesRef will have a length of other.length and an offset of zero.

func NewBytesRef 

func NewBytesRef(bytes []byte, offset, length int) *BytesRef

func NewBytesRefFrom 

func NewBytesRefFrom(bytes []byte) *BytesRef

func NewEmptyBytesRef 

func NewEmptyBytesRef() *BytesRef

func (*BytesRef) String 

func (br *BytesRef) String() string

func (*BytesRef) ToBytes 

func (br *BytesRef) ToBytes() []byte

type BytesRefBuilder 

type BytesRefBuilder struct {
	// contains filtered or unexported fields
}

func NewBytesRefBuilder 

func NewBytesRefBuilder() *BytesRefBuilder

func (*BytesRefBuilder) At 

func (b *BytesRefBuilder) At(offset int) byte

Return the byte at the given offset.

func (*BytesRefBuilder) Bytes 

func (b *BytesRefBuilder) Bytes() []byte

Return a reference to the bytes of this build.

func (*BytesRefBuilder) Copy 

func (b *BytesRefBuilder) Copy(ref []byte)

func (*BytesRefBuilder) Get 

func (b *BytesRefBuilder) Get() *BytesRef

func (*BytesRefBuilder) Grow 

func (b *BytesRefBuilder) Grow(capacity int)

Ensure that this builder can hold at least capacity bytes without resizing.

func (*BytesRefBuilder) Length 

func (b *BytesRefBuilder) Length() int

Return the number of bytes in this buffer.

func (*BytesRefBuilder) Set 

func (b *BytesRefBuilder) Set(offset int, v byte)

Set a byte.

func (*BytesRefBuilder) SetLength 

func (b *BytesRefBuilder) SetLength(length int)

Set the length.

type BytesRefHash 

type BytesRefHash struct {
	// contains filtered or unexported fields
}

BytesRefHash is a special purpose hash map like data structure optimized for BytesRef instances. BytesRefHash maintains mappings of byte arrays to ids (map[[]byte]int) sorting the hashed bytes efficiently in continuous storage. The mapping to the id is encapsulated inside BytesRefHash and is guaranteed to be increased for each added BytesRef.

Note: The maximum capacity BytesRef instance passed to add() must not be longer than BYTE_BLOCK_SIZE-2. The internal storage is limited to 2GB total byte storage.

func NewBytesRefHash 

func NewBytesRefHash(pool *ByteBlockPool, capacity int,
	bytesStartArray BytesStartArray) *BytesRefHash

func (*BytesRefHash) Add 

func (h *BytesRefHash) Add(bytes []byte) (int, error)

Adds a new BytesRef.

func (*BytesRefHash) ByteStart 

func (h *BytesRefHash) ByteStart(bytesId int) int

Returns the bytesStart offset into the internally used ByteBlockPool for the given bytesID.

func (*BytesRefHash) Clear 

func (h *BytesRefHash) Clear(resetPool bool)

Clears the BytesRef which maps to the given BytesRef

func (*BytesRefHash) Reinit 

func (h *BytesRefHash) Reinit()

reinitializes the BytesRefHash after a previous clear() call. If clear() has not been called previously this method has no effect.

func (*BytesRefHash) Size 

func (h *BytesRefHash) Size() int

Returns the number of values in this hash.

func (*BytesRefHash) Sort 

func (h *BytesRefHash) Sort(comp func(a, b []byte) bool) []int

Returns the values array sorted by the referenced byte values.

Note: this is a destructive operation. clear() must be called in order to reuse this BytesRefHash instance.

type BytesRefIterator 

type BytesRefIterator interface {
	/* Increments the iteration to the next []byte in the iterator. Returns the
	resulting []byte or nil if the end of the iterator is reached. The returned
	[]byte may be re-used across calls to the next. After this method returns
	nil, do not call it again: the results are undefined. */
	Next() (buf []byte, err error)

	/* Return the []byte Comparator used to sort terms provided by the iterator.
	This may return nil if there are no items or the iterator is not sorted.
	Callers may invoke this method many times, so it's best to cache a single
	instance & reuse it. */
	Comparator() sort.Interface
}

BytesRefIterator.java A simple iterator interface for []byte iteration.

type BytesRefs 

type BytesRefs [][]byte

func (BytesRefs) Len 

func (br BytesRefs) Len() int

func (BytesRefs) Less 

func (br BytesRefs) Less(i, j int) bool

func (BytesRefs) Swap 

func (br BytesRefs) Swap(i, j int)

type BytesStartArray 

type BytesStartArray interface {
	// Initializes the BytesStartArray. This call will allocate memory
	Init() []int
	// A Counter reference holding the number of bytes used by this
	// BytesStartArray. The BytesRefHash uses this reference to track
	// its memory usage
	BytesUsed() Counter
	// Grows the BytesStartArray
	Grow() []int
	// clears the BytesStartArray and returns the cleared instance.
	Clear() []int
}

Manages allocation of per-term addresses.

type CompoundError 

type CompoundError struct {
	// contains filtered or unexported fields
}

func (*CompoundError) Error 

func (e *CompoundError) Error() string

type Counter 

type Counter interface {
	AddAndGet(delta int64) int64
	Get() int64
}

func NewAtomicCounter 

func NewAtomicCounter() Counter

func NewCounter 

func NewCounter() Counter

type DataInput 

type DataInput interface {
	ReadByte() (b byte, err error)
	ReadBytes(buf []byte) error
	ReadShort() (n int16, err error)
	ReadInt() (n int32, err error)
	ReadVInt() (n int32, err error)
	ReadLong() (n int64, err error)
	ReadVLong() (n int64, err error)
	ReadString() (s string, err error)
	ReadStringStringMap() (m map[string]string, err error)
	ReadStringSet() (m map[string]bool, err error)
}

Abstract base class for performing read operations of Lucene's low-level data types.

DataInput may only be used from one thread, because it is not thread safe (it keeps internal state like file position). To allow multithreaded use, every DataInput instance must be cloned before used in another thread. Subclases must therefore implement Clone(), returning a new DataInput which operates on the same underlying resource, but positioned independently.

type DataInputImpl 

type DataInputImpl struct {
	Reader DataReader
	// contains filtered or unexported fields
}

func NewDataInput 

func NewDataInput(spi DataReader) *DataInputImpl

func (*DataInputImpl) ReadBytesBuffered 

func (in *DataInputImpl) ReadBytesBuffered(buf []byte, useBuffer bool) error

func (*DataInputImpl) ReadInt 

func (in *DataInputImpl) ReadInt() (n int32, err error)

func (*DataInputImpl) ReadLong 

func (in *DataInputImpl) ReadLong() (n int64, err error)

func (*DataInputImpl) ReadShort 

func (in *DataInputImpl) ReadShort() (n int16, err error)

func (*DataInputImpl) ReadString 

func (in *DataInputImpl) ReadString() (s string, err error)

func (*DataInputImpl) ReadStringSet 

func (in *DataInputImpl) ReadStringSet() (s map[string]bool, err error)

func (*DataInputImpl) ReadStringStringMap 

func (in *DataInputImpl) ReadStringStringMap() (m map[string]string, err error)

func (*DataInputImpl) ReadVInt 

func (in *DataInputImpl) ReadVInt() (n int32, err error)

func (*DataInputImpl) ReadVLong 

func (in *DataInputImpl) ReadVLong() (int64, error)

func (*DataInputImpl) SkipBytes 

func (in *DataInputImpl) SkipBytes(numBytes int64) (err error)

Skip over numBytes bytes. The contract on this method is that it should have the same behavior as reading the same number of bytes into a buffer and discarding its content. Negative values of numBytes are not supported.

type DataOutput 

type DataOutput interface {
	DataWriter
	WriteInt(i int32) error
	WriteVInt(i int32) error
	WriteLong(i int64) error
	WriteVLong(i int64) error
	WriteString(s string) error
	CopyBytes(input DataInput, numBytes int64) error
	WriteStringStringMap(m map[string]string) error
	WriteStringSet(m map[string]bool) error
}

Abstract base class for performing write operations of Lucene's low-level data types.

DataOutput may only be used from one thread, because it is not thread safe (it keeps internal state like file position).

type DataOutputImpl 

type DataOutputImpl struct {
	Writer DataWriter
	// contains filtered or unexported fields
}

func NewDataOutput 

func NewDataOutput(part DataWriter) *DataOutputImpl

func (*DataOutputImpl) CopyBytes 

func (out *DataOutputImpl) CopyBytes(input DataInput, numBytes int64) error

func (*DataOutputImpl) WriteInt 

func (out *DataOutputImpl) WriteInt(i int32) error

Writes an int as four bytes.

32-bit unsigned integer written as four bytes, high-order bytes first.

func (*DataOutputImpl) WriteLong 

func (out *DataOutputImpl) WriteLong(i int64) error

Writes a long as eight bytes.

64-bit unsigned integer written as eight bytes, high-order bytes first.

func (*DataOutputImpl) WriteString 

func (out *DataOutputImpl) WriteString(s string) error

Writes a string.

Writes strings as UTF-8 encoded bytes. First the length, in bytes, is written as a VInt, followed by the bytes.

func (*DataOutputImpl) WriteStringSet 

func (out *DataOutputImpl) WriteStringSet(m map[string]bool) error

Writes a String set.

First the size is written as an int32, followed by each value written as a string.

func (*DataOutputImpl) WriteStringStringMap 

func (out *DataOutputImpl) WriteStringStringMap(m map[string]string) error

Writes a string map.

First the size is written as an int32, followed by each key-value pair written as two consecutive strings.

func (*DataOutputImpl) WriteVInt 

func (out *DataOutputImpl) WriteVInt(i int32) error

Writes an int in a variable-length format. Writes between one and five bytes. Smaller values take fewer bytes. Negative numbers are supported, by should be avoided.

VByte is a variable-length format. For positive integers, it is defined where the high-order bit of each byte indicates whether more bytes remain to be read. The low-order seven bits are appended as increasingly more significant bits in the resulting integer value. Thus values from zero to 127 may be stored in a single byte, values from 128 to 16,383 may be stored in two bytes, and so on.

VByte Encoding Examle 

| Value		| Byte 1		| Byte 2		| Byte 3		|
| 0				| 00000000	|
| 1				| 00000001	|
| 2				| 00000010	|
| ...			|
| 127			| 01111111	|
| 128			| 10000000	| 00000001	|
| 129			| 10000001	| 00000001	|
| 130			| 10000010	| 00000001	|
| ...			|
| 16,383	| 11111111	| 01111111	|
| 16,384	| 10000000	| 10000000	| 00000001	|
| 16,385	| 10000001	| 10000000	| 00000001	|
| ...			|

This provides compression while still being efficient to decode.

func (*DataOutputImpl) WriteVLong 

func (out *DataOutputImpl) WriteVLong(i int64) error

Writes an long in a variable-length format. Writes between one and none bytes. Smaller values take fewer bytes. Negative number are not supported.

The format is described further in WriteVInt().

type DataReader 

type DataReader interface {
	/* Reads and returns a single byte.	*/
	ReadByte() (b byte, err error)
	/* Reads a specified number of bytes into an array */
	ReadBytes(buf []byte) error
}

type DataWriter 

type DataWriter interface {
	WriteByte(b byte) error
	WriteBytes(buf []byte) error
}

type DirectTrackingAllocator 

type DirectTrackingAllocator struct {
	*ByteAllocatorImpl
	// contains filtered or unexported fields
}

A simple Allocator that never recycles, but tracks how much total RAM is in use.

func NewDirectTrackingAllocator 

func NewDirectTrackingAllocator(bytesUsed Counter) *DirectTrackingAllocator

type FileDeleter 

type FileDeleter interface {
	DeleteFile(name string) error
}

type FixedBitSet 

type FixedBitSet struct {
	// contains filtered or unexported fields
}

BitSet of fixed length (numBits), backed by accessible bits() []int64, accessed with an int index, implementing Bits and DocIdSet. Unlike OpenBitSet, this bit set does not auto-expand, cannot handle long index, and does not have fastXX/XX variants (just X).

func EnsureFixedBitSet 

func EnsureFixedBitSet(bits *FixedBitSet, numBits int) *FixedBitSet

If the given FixedBitSet is large enough to hold numBits, returns the given bits, otherwise returns a new FixedBitSet which can hold the rquired number of bits.

NOTE: the returned bitset reuses the underlying []int64 of the given bits if possible. Also, calling length() on the returned bits may return a value greater than numBits.

func NewFixedBitSetOf 

func NewFixedBitSetOf(numBits int) *FixedBitSet

func (*FixedBitSet) At 

func (b *FixedBitSet) At(index int) bool

func (*FixedBitSet) Bits 

func (b *FixedBitSet) Bits() Bits

func (*FixedBitSet) Cardinality 

func (b *FixedBitSet) Cardinality() int

Returns number of set bits. NOTE: this visits every int64 in the backing bits slice, and the result is not internaly cached!

func (*FixedBitSet) IsCacheable 

func (b *FixedBitSet) IsCacheable() bool

func (*FixedBitSet) Length 

func (b *FixedBitSet) Length() int

func (*FixedBitSet) RamBytesUsed 

func (b *FixedBitSet) RamBytesUsed() int64

func (*FixedBitSet) Set 

func (b *FixedBitSet) Set(index int)

type InPlaceMergeSorter 

type InPlaceMergeSorter struct {
	*Sorter
}

Sorter implementation absed on the merge-sort algorithm that merges in place (no extra memory will be allocated). Small arrays are sorter with insertion sort.

func NewInPlaceMergeSorter 

func NewInPlaceMergeSorter(impl sort.Interface) *InPlaceMergeSorter

func (*InPlaceMergeSorter) Sort 

func (s *InPlaceMergeSorter) Sort(from, to int)

type InfoStream 

type InfoStream interface {
	io.Closer
	// Clone() InfoStream
	// prints a message
	Message(component, message string, args ...interface{})
	// returns true if messages are enabled and should be posted.
	IsEnabled(component string) bool
}

Debugging API for Lucene classes such as IndexWriter and SegmentInfos.

NOTE: Enabling infostreams may cause performance degradation in some components.

func DefaultInfoStream 

func DefaultInfoStream() InfoStream

The default InfoStream used by a newly instantiated classes.

type IntAllocator 

type IntAllocator interface {
	Recycle(blocks [][]int)
	// contains filtered or unexported methods
}

type IntAllocatorImpl 

type IntAllocatorImpl struct {
	// contains filtered or unexported fields
}

func NewIntAllocator 

func NewIntAllocator(blockSize int) *IntAllocatorImpl

type IntBlockPool 

type IntBlockPool struct {
	Buffers [][]int

	IntUpto   int
	Buffer    []int
	IntOffset int
	// contains filtered or unexported fields
}

A pool for int blocks similar to ByteBlockPool

func NewIntBlockPool 

func NewIntBlockPool(allocator IntAllocator) *IntBlockPool

func (*IntBlockPool) NextBuffer 

func (p *IntBlockPool) NextBuffer()

Advances the pool to its next buffer. This mthod should be called once after the constructor to initialize the pool. In contrast to the constructor a IntBlockPool.reset() call will advance the pool to its first buffer immediately.

func (*IntBlockPool) Reset 

func (pool *IntBlockPool) Reset(zeroFillBuffers, reuseFirst bool)

Expert: Resets the pool to its initial state reusing the first buffer.

type IntroSorter 

type IntroSorter struct {
	*Sorter
	// contains filtered or unexported fields
}

Sorter implementation based on a variant of the quicksort algorithm called introsort: when the recursion level exceeds the log of the length of the array to sort, it falls back to heapsort. This prevents quicksort from running into its worst-case quadratic runtime. Small arrays are sorted with insertion sort.

func NewIntroSorter 

func NewIntroSorter(spi IntroSorterSPI, arr sort.Interface) *IntroSorter

func (*IntroSorter) Sort 

func (s *IntroSorter) Sort(from, to int)

type IntroSorterSPI 

type IntroSorterSPI interface {
	// Save the value at slot i so that it can later be used as a pivot.
	SetPivot(int)
	// Compare the pivot with the slot at j, similarly to Less(int,int).
	PivotLess(int) bool
}

type IntsRef 

type IntsRef struct {
	// The contents of teh IntsRef. Should never be nil.
	Ints []int
	// Offset of first valid integer.
	Offset int
	// Length of used ints.
	Length int
}

Represents []int, as a slice (offset + length) into an existing []int. The ints member should never be nil; use EMPTY_INTS if necessary.

Go's native slice is always preferrable unless the reference pointer need to remain unchanged, in which case, this class is more useful.

func NewEmptyIntsRef 

func NewEmptyIntsRef() *IntsRef

func (*IntsRef) At 

func (a *IntsRef) At(i int) int

func (*IntsRef) CopyInts 

func (a *IntsRef) CopyInts(other *IntsRef)

func (*IntsRef) Grow 

func (a *IntsRef) Grow(newLength int)

Used to grow the reference slice.

In general this should not be used as it does not take the offset into account.

func (*IntsRef) Less 

func (a *IntsRef) Less(other *IntsRef) bool

Signed int order comparison

func (*IntsRef) Value 

func (a *IntsRef) Value() []int

type IntsRefBuilder 

type IntsRefBuilder struct {
	// contains filtered or unexported fields
}

func NewIntsRefBuilder 

func NewIntsRefBuilder() *IntsRefBuilder

func (*IntsRefBuilder) Append 

func (a *IntsRefBuilder) Append(i int)

func (*IntsRefBuilder) At 

func (a *IntsRefBuilder) At(offset int) int

func (*IntsRefBuilder) Clear 

func (a *IntsRefBuilder) Clear()

func (*IntsRefBuilder) CopyIntSlice 

func (a *IntsRefBuilder) CopyIntSlice(other []int)

func (*IntsRefBuilder) CopyInts 

func (a *IntsRefBuilder) CopyInts(ints *IntsRef)

func (*IntsRefBuilder) Get 

func (a *IntsRefBuilder) Get() *IntsRef

func (*IntsRefBuilder) Grow 

func (a *IntsRefBuilder) Grow(newLength int)

func (*IntsRefBuilder) Length 

func (a *IntsRefBuilder) Length() int

type ListIntroSorter 

type ListIntroSorter struct {
	*IntroSorter
}

func (*ListIntroSorter) PivotLess 

func (s *ListIntroSorter) PivotLess(j int) bool

func (*ListIntroSorter) SetPivot 

func (s *ListIntroSorter) SetPivot(i int)

type MaxBytesLengthExceededError 

type MaxBytesLengthExceededError string

func (MaxBytesLengthExceededError) Error 

func (e MaxBytesLengthExceededError) Error() string

type MutableBits 

type MutableBits interface {
	Bits
	// Sets the bit specified by index to false.
	Clear(index int)
}

Extension of Bits for live documents.

type NoOutput 

type NoOutput bool

func (NoOutput) Close 

func (is NoOutput) Close() error

func (NoOutput) IsEnabled 

func (is NoOutput) IsEnabled(component string) bool

func (NoOutput) Message 

func (is NoOutput) Message(component, message string, args ...interface{})

type OpenBitSet 

type OpenBitSet struct {
	// contains filtered or unexported fields
}

func NewOpenBitSet 

func NewOpenBitSet() *OpenBitSet

func NewOpenBitSetOf 

func NewOpenBitSetOf(numBits int64) *OpenBitSet

Constructs an OpenBitSet large enough to hold numBits.

func (*OpenBitSet) And 

func (b *OpenBitSet) And(other *OpenBitSet)

func (*OpenBitSet) AndNot 

func (b *OpenBitSet) AndNot(other *OpenBitSet)

func (*OpenBitSet) Cardinality 

func (b *OpenBitSet) Cardinality() int64

L553 

Return the number of set bits

func (*OpenBitSet) Clear 

func (b *OpenBitSet) Clear(index int64)

Clears a bit, allowing access beyond the current set size without changing the size.

func (*OpenBitSet) Get 

func (b *OpenBitSet) Get(index int64) bool

Returns true or false for the specified bit index

func (*OpenBitSet) IsEmpty 

func (b *OpenBitSet) IsEmpty() bool

Returns true if there are no set bits

func (*OpenBitSet) NextSetBit 

func (b *OpenBitSet) NextSetBit(index int64) int64

Returns the index of the first set bit starting at the index specified. - is returned if there are no more set bits.

func (*OpenBitSet) Set 

func (b *OpenBitSet) Set(index int64)

Sets a bit, expanding the set size if necessary

func (*OpenBitSet) String 

func (b *OpenBitSet) String() string

type PrintStreamInfoStream 

type PrintStreamInfoStream struct {
	// contains filtered or unexported fields
}

InfoStream implementation over an io.Writer such as os.Stdout

func NewPrintStreamInfoStream 

func NewPrintStreamInfoStream(w io.Writer) *PrintStreamInfoStream

func (*PrintStreamInfoStream) Close 

func (is *PrintStreamInfoStream) Close() error

func (*PrintStreamInfoStream) IsEnabled 

func (is *PrintStreamInfoStream) IsEnabled(component string) bool

func (*PrintStreamInfoStream) Message 

func (is *PrintStreamInfoStream) Message(component,
	message string, args ...interface{})

type SetOnce 

type SetOnce struct {
	*sync.Once
	// contains filtered or unexported fields
}

A convenient class which offers a semi-immutable object wrapper implementation which allows one to set the value of an object exactly once, and retrieve it many times. If Set() is called more than once, error is returned and the operation will fail.

func NewSetOnce 

func NewSetOnce() *SetOnce

func NewSetOnceOf 

func NewSetOnceOf(obj interface{}) *SetOnce

func (*SetOnce) Clone 

func (so *SetOnce) Clone() *SetOnce

func (*SetOnce) Get 

func (so *SetOnce) Get() interface{}

Returns the object set by Set().

func (*SetOnce) Set 

func (so *SetOnce) Set(obj interface{})

Sets the given object. If the object has already been set, an exception is thrown.

func (*SetOnce) String 

func (so *SetOnce) String() string

type Sorter 

type Sorter struct {
	sort.Interface
}

Base class for sorting algorithms implementations.

type TimSorter 

type TimSorter struct {
	*Sorter
	// contains filtered or unexported fields
}

Sorter implementation based on TimSorter(http://svn.python.org/projects/python/trunk/Objects/listsort.txt) algorithm.

This implementation is especially good at sorting partially-sorted arrays and sorts small arrays with binary sort.

NOTE: There are a few differences with the original implementation:

1. The extra amount of memory to perform merges is configurable. This allows small merges to be very fast while large merges will be performed in-place (slightly slower). You can make sure that the fast merge routine will always be used by having maxTempSlots equal to half of the length of the slice of data to sort.

2. Only the fast merge routine can gallop (the one that doesn't in-place) and it only gallops on the longest slice.

type Version 

type Version [4]int

func ParseVersion 

func ParseVersion(version string) (ver Version, err error)

Parse a version number of the form major.minor.bugfix.prerlease

Part .bugfix and part .prerelease are optional. Note that this is forwards compatible: the parsed version does not have to exist as a constant.

func (Version) Equals 

func (v Version) Equals(other Version) bool

func (Version) OnOrAfter 

func (v Version) OnOrAfter(other Version) bool

func (Version) String 

func (v Version) String() string

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