scriptoriumadmin/featurebase
1
0
Fork 0
mirror of https://github.com/featurebasedb/featurebase.git synced 2026-09-07 09:05:55 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

B+tree integration work.

Browse source 
Export necessary vars from roaring to fix b+tree containers implementation.
Clean up naming.
Use constructor replacement for enterprise integration.
This commit is contained in:
Cody Soyland 2018-05-14 17:32:30 -05:00
parent 4282e90fe1
commit 513c7fd705
9 changed files with 110 additions and 104 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

22
enterprise/b/containers_btree.go
View file

@ -2,6 +2,7 @@ package b
import (
"io"
"log"
"github.com/pilosa/pilosa/roaring"
)
@ -10,17 +11,26 @@ func cmp(a, b uint64) int {
return int(a - b)
}
type BTreeContainers struct {
tree *Tree
lastKey uint64
lastContainer *roaring.Container
}
func NewBTreeContainers() *BTreeContainers {
return &BTreeContainers{
tree: TreeNew(cmp),
}
}
type BTreeContainers struct {
tree *Tree
lastKey uint64
lastContainer *roaring.Container
func NewBTreeBitmap(a ...uint64) *roaring.Bitmap {
log.Println("btree bitmap")
b := &roaring.Bitmap{
Containers: NewBTreeContainers(),
}
b.Add(a...)
return b
}
func (btc *BTreeContainers) Get(key uint64) *roaring.Container {
@ -96,7 +106,7 @@ func (btc *BTreeContainers) GetOrCreate(key uint64) *roaring.Container {
return btc.lastContainer
}
func (btc *BTreeContainers) Clone() roaring.Containerser {
func (btc *BTreeContainers) Clone() roaring.Containers {
nbtc := NewBTreeContainers()
itr, err := btc.tree.SeekFirst()

2
fragment.go
View file

@ -189,7 +189,7 @@ func (f *Fragment) Open() error {
func (f *Fragment) openStorage() error {
// Create a roaring bitmap to serve as storage for the slice.
if f.storage == nil {
f.storage = roaring.NewBitmap()
f.storage = roaring.NewFileBitmap()
}
// Open the data file to be mmap'd and used as an ops log.
file, err := os.OpenFile(f.path, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)

8
roaring/containers.go
View file

@ -7,6 +7,10 @@ type SliceContainers struct {
lastContainer *Container
}
func NewSliceContainers() *SliceContainers {
return &SliceContainers{}
}
func (sc *SliceContainers) Get(key uint64) *Container {
i := search64(sc.keys, key)
if i < 0 {
@ -83,8 +87,8 @@ func (sc *SliceContainers) GetOrCreate(key uint64) *Container {
return sc.lastContainer
}
func (sc *SliceContainers) Clone() Containerser {
other := NewContainers()
func (sc *SliceContainers) Clone() Containers {
other := NewSliceContainers()
other.keys = make([]uint64, len(sc.keys))
other.containers = make([]*Container, len(sc.containers))
copy(other.keys, sc.keys)

9
roaring/containers_btree.go
View file

@ -1,9 +0,0 @@
// +build enterprise
package roaring
import "github.com/pilosa/pilosa/enterprise/b"
func NewContainers() *b.BTreeContainers {
return &b.BTreeContainers{}
}

7
roaring/containers_slice.go
View file

@ -1,7 +0,0 @@
// +build !enterprise
package roaring
func NewContainers() *SliceContainers {
return &SliceContainers{}
}

4
roaring/containers_test.go
View file

@ -9,11 +9,11 @@ import (
// testContainersIterator(btc, t)
//}
func TestContainersBTreeIterator(t *testing.T) {
slc := NewContainers()
slc := NewSliceContainers()
testContainersIterator(slc, t)
}
func testContainersIterator(cs Containerser, t *testing.T) {
func testContainersIterator(cs Containers, t *testing.T) {
itr, found := cs.Iterator(0)
if found {
t.Fatalf("shouldn't have found 0 in empty btc")

111
roaring/roaring.go
View file

@ -64,7 +64,7 @@ const (
maxContainerVal = 0xffff
)
type Containerser interface {
type Containers interface {
// Get returns nil if the key does not exist.
Get(key uint64) *Container
@ -82,7 +82,7 @@ type Containerser interface {
GetOrCreate(key uint64) *Container
// Clone does a deep copy of Containers, including cloning all containers contained.
Clone() Containerser
Clone() Containers
// Last returns the highest key and associated container.
Last() (key uint64, c *Container)
@ -103,7 +103,7 @@ type Contiterator interface {
// Bitmap represents a roaring bitmap.
type Bitmap struct {
conts Containerser
Containers Containers
// Number of operations written to the writer.
opN int
@ -115,19 +115,14 @@ type Bitmap struct {
// NewBitmap returns a Bitmap with an initial set of values.
func NewBitmap(a ...uint64) *Bitmap {
b := &Bitmap{
conts: NewContainers(),
Containers: NewSliceContainers(),
}
b.Add(a...)
return b
}
//func NewBTreeBitmap(a ...uint64) *Bitmap {
// b := &Bitmap{
// conts: NewBTreeContainers(),
// }
// b.Add(a...)
// return b
//}
// NewFileBitmap returns a Bitmap with an initial set of values.
var NewFileBitmap func(a ...uint64) *Bitmap = NewBitmap
// Clone returns a heap allocated copy of the bitmap.
// Note: The OpWriter IS NOT copied to the new bitmap.
@ -138,7 +133,7 @@ func (b *Bitmap) Clone() *Bitmap {
// Create a copy of the bitmap structure.
other := &Bitmap{
conts: b.conts.Clone(),
Containers: b.Containers.Clone(),
}
return other
@ -167,13 +162,13 @@ func (b *Bitmap) Add(a ...uint64) (changed bool, err error) {
}
func (b *Bitmap) add(v uint64) bool {
cont := b.conts.GetOrCreate(highbits(v))
cont := b.Containers.GetOrCreate(highbits(v))
return cont.add(lowbits(v))
}
// Contains returns true if v is in the bitmap.
func (b *Bitmap) Contains(v uint64) bool {
c := b.conts.Get(highbits(v))
c := b.Containers.Get(highbits(v))
if c == nil {
return false
}
@ -201,7 +196,7 @@ func (b *Bitmap) Remove(a ...uint64) (changed bool, err error) {
}
func (b *Bitmap) remove(v uint64) bool {
c := b.conts.Get(highbits(v))
c := b.Containers.Get(highbits(v))
if c == nil {
return false
}
@ -212,18 +207,18 @@ func (b *Bitmap) remove(v uint64) bool {
// Max returns the highest value in the bitmap.
// Returns zero if the bitmap is empty.
func (b *Bitmap) Max() uint64 {
if b.conts.Size() == 0 {
if b.Containers.Size() == 0 {
return 0
}
hb, c := b.conts.Last()
hb, c := b.Containers.Last()
lb := c.max()
return hb<<16 | uint64(lb)
}
// Count returns the number of bits set in the bitmap.
func (b *Bitmap) Count() (n uint64) {
citer, _ := b.conts.Iterator(0)
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
_, c := citer.Value()
n += uint64(c.n)
@ -233,14 +228,14 @@ func (b *Bitmap) Count() (n uint64) {
// CountRange returns the number of bits set between [start, end).
func (b *Bitmap) CountRange(start, end uint64) (n uint64) {
if b.conts.Size() == 0 {
if b.Containers.Size() == 0 {
return
}
skey := highbits(start)
ekey := highbits(end)
citer, found := b.conts.Iterator(highbits(start))
citer, found := b.Containers.Iterator(highbits(start))
// If range is entirely in one container then just count that range.
if found && skey == ekey {
citer.Next()
@ -328,21 +323,21 @@ func (b *Bitmap) OffsetRange(offset, start, end uint64) *Bitmap {
off := highbits(offset)
hi0, hi1 := highbits(start), highbits(end)
citer, _ := b.conts.Iterator(hi0)
citer, _ := b.Containers.Iterator(hi0)
other := NewBitmap()
for citer.Next() {
k, c := citer.Value()
if k >= hi1 {
break
}
other.conts.Put(off+(k-hi0), c)
other.Containers.Put(off+(k-hi0), c)
}
return other
}
// container returns the container with the given key.
func (b *Bitmap) container(key uint64) *Container {
return b.conts.Get(key)
return b.Containers.Get(key)
}
// IntersectionCount returns the number of set bits that would result in an
@ -350,8 +345,8 @@ func (b *Bitmap) container(key uint64) *Container {
// intersecting the two and counting the result.
func (b *Bitmap) IntersectionCount(other *Bitmap) uint64 {
var n uint64
iiter, _ := b.conts.Iterator(0)
jiter, _ := other.conts.Iterator(0)
iiter, _ := b.Containers.Iterator(0)
jiter, _ := other.Containers.Iterator(0)
i, j := iiter.Next(), jiter.Next()
ki, ci := iiter.Value()
kj, cj := jiter.Value()
@ -375,8 +370,8 @@ func (b *Bitmap) IntersectionCount(other *Bitmap) uint64 {
// Intersect returns the intersection of b and other.
func (b *Bitmap) Intersect(other *Bitmap) *Bitmap {
output := NewBitmap()
iiter, _ := b.conts.Iterator(0)
jiter, _ := other.conts.Iterator(0)
iiter, _ := b.Containers.Iterator(0)
jiter, _ := other.Containers.Iterator(0)
i, j := iiter.Next(), jiter.Next()
ki, ci := iiter.Value()
kj, cj := jiter.Value()
@ -388,7 +383,7 @@ func (b *Bitmap) Intersect(other *Bitmap) *Bitmap {
j = jiter.Next()
kj, cj = jiter.Value()
} else { // ki == kj
output.conts.Put(ki, intersect(ci, cj))
output.Containers.Put(ki, intersect(ci, cj))
i, j = iiter.Next(), jiter.Next()
ki, ci = iiter.Value()
kj, cj = jiter.Value()
@ -401,22 +396,22 @@ func (b *Bitmap) Intersect(other *Bitmap) *Bitmap {
func (b *Bitmap) Union(other *Bitmap) *Bitmap {
output := NewBitmap()
iiter, _ := b.conts.Iterator(0)
jiter, _ := other.conts.Iterator(0)
iiter, _ := b.Containers.Iterator(0)
jiter, _ := other.Containers.Iterator(0)
i, j := iiter.Next(), jiter.Next()
ki, ci := iiter.Value()
kj, cj := jiter.Value()
for i || j {
if i && (!j || ki < kj) {
output.conts.Put(ki, ci.Clone())
output.Containers.Put(ki, ci.Clone())
i = iiter.Next()
ki, ci = iiter.Value()
} else if j && (!i || ki > kj) {
output.conts.Put(kj, cj.Clone())
output.Containers.Put(kj, cj.Clone())
j = jiter.Next()
kj, cj = jiter.Value()
} else { // ki == kj
output.conts.Put(ki, union(ci, cj))
output.Containers.Put(ki, union(ci, cj))
i, j = iiter.Next(), jiter.Next()
ki, ci = iiter.Value()
kj, cj = jiter.Value()
@ -429,21 +424,21 @@ func (b *Bitmap) Union(other *Bitmap) *Bitmap {
func (b *Bitmap) Difference(other *Bitmap) *Bitmap {
output := NewBitmap()
iiter, _ := b.conts.Iterator(0)
jiter, _ := other.conts.Iterator(0)
iiter, _ := b.Containers.Iterator(0)
jiter, _ := other.Containers.Iterator(0)
i, j := iiter.Next(), jiter.Next()
ki, ci := iiter.Value()
kj, cj := jiter.Value()
for i || j {
if i && (!j || ki < kj) {
output.conts.Put(ki, ci.Clone())
output.Containers.Put(ki, ci.Clone())
i = iiter.Next()
ki, ci = iiter.Value()
} else if j && (!i || ki > kj) {
j = jiter.Next()
kj, cj = jiter.Value()
} else { // ki == kj
output.conts.Put(ki, difference(ci, cj))
output.Containers.Put(ki, difference(ci, cj))
i, j = iiter.Next(), jiter.Next()
ki, ci = iiter.Value()
kj, cj = jiter.Value()
@ -456,22 +451,22 @@ func (b *Bitmap) Difference(other *Bitmap) *Bitmap {
func (b *Bitmap) Xor(other *Bitmap) *Bitmap {
output := NewBitmap()
iiter, _ := b.conts.Iterator(0)
jiter, _ := other.conts.Iterator(0)
iiter, _ := b.Containers.Iterator(0)
jiter, _ := other.Containers.Iterator(0)
i, j := iiter.Next(), jiter.Next()
ki, ci := iiter.Value()
kj, cj := jiter.Value()
for i || j {
if i && (!j || ki < kj) {
output.conts.Put(ki, ci.Clone())
output.Containers.Put(ki, ci.Clone())
i = iiter.Next()
ki, ci = iiter.Value()
} else if j && (!i || ki > kj) {
output.conts.Put(kj, cj.Clone())
output.Containers.Put(kj, cj.Clone())
j = jiter.Next()
kj, cj = jiter.Value()
} else { // ki == kj
output.conts.Put(ki, xor(ci, cj))
output.Containers.Put(ki, xor(ci, cj))
i, j = iiter.Next(), jiter.Next()
ki, ci = iiter.Value()
kj, cj = jiter.Value()
@ -482,17 +477,17 @@ func (b *Bitmap) Xor(other *Bitmap) *Bitmap {
// removeEmptyContainers deletes all containers that have a count of zero.
func (b *Bitmap) removeEmptyContainers() {
citer, _ := b.conts.Iterator(0)
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
k, c := citer.Value()
if c.n == 0 {
b.conts.Remove(k)
b.Containers.Remove(k)
}
}
}
func (b *Bitmap) countEmptyContainers() int {
result := 0
citer, _ := b.conts.Iterator(0)
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
_, c := citer.Value()
if c.n == 0 {
@ -504,7 +499,7 @@ func (b *Bitmap) countEmptyContainers() int {
// Optimize converts array and bitmap containers to run containers as necessary.
func (b *Bitmap) Optimize() {
citer, _ := b.conts.Iterator(0)
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
_, c := citer.Value()
c.Optimize()
@ -552,7 +547,7 @@ func (b *Bitmap) WriteTo(w io.Writer) (n int64, err error) {
// Remove empty containers before persisting.
//b.removeEmptyContainers()
containerCount := b.conts.Size() - b.countEmptyContainers()
containerCount := b.Containers.Size() - b.countEmptyContainers()
headerSize := headerBaseSize
byte2 := make([]byte, 2)
byte4 := make([]byte, 4)
@ -571,7 +566,7 @@ func (b *Bitmap) WriteTo(w io.Writer) (n int64, err error) {
// Descriptive header section: encode keys and cardinality.
// Key and cardinality are stored interleaved here, 12 bytes per container.
citer, _ := b.conts.Iterator(0)
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
key, c := citer.Value()
// Verify container count before writing.
@ -589,7 +584,7 @@ func (b *Bitmap) WriteTo(w io.Writer) (n int64, err error) {
// Offset header section: write the offset for each container block.
// 4 bytes per container.
offset := uint32(headerSize + (containerCount * (8 + 2 + 2 + 4)))
citer, _ = b.conts.Iterator(0)
citer, _ = b.Containers.Iterator(0)
for citer.Next() {
_, c := citer.Value()
if c.n > 0 {
@ -605,7 +600,7 @@ func (b *Bitmap) WriteTo(w io.Writer) (n int64, err error) {
n = int64(headerSize + (containerCount * (8 + 2 + 2 + 4)))
// Container storage section: write each container block.
citer, _ = b.conts.Iterator(0)
citer, _ = b.Containers.Iterator(0)
for citer.Next() {
_, c := citer.Value()
if c.n > 0 {
@ -643,7 +638,7 @@ func (b *Bitmap) UnmarshalBinary(data []byte) error {
// Descriptive header section: Read container keys and cardinalities.
for i, buf := 0, data[headerSize:]; i < int(keyN); i, buf = i+1, buf[12:] {
b.conts.PutContainerValues(
b.Containers.PutContainerValues(
binary.LittleEndian.Uint64(buf[0:8]),
byte(binary.LittleEndian.Uint16(buf[8:10])),
int(binary.LittleEndian.Uint16(buf[10:12]))+1,
@ -652,7 +647,7 @@ func (b *Bitmap) UnmarshalBinary(data []byte) error {
opsOffset := headerSize + int(keyN)*12
// Read container offsets and attach data.
citer, _ := b.conts.Iterator(0)
citer, _ := b.Containers.Iterator(0)
for i, buf := 0, data[opsOffset:]; i < int(keyN); i, buf = i+1, buf[4:] {
offset := binary.LittleEndian.Uint32(buf[0:4])
// Verify the offset is within the bounds of the input data.
@ -734,10 +729,10 @@ func (b *Bitmap) Iterator() *Iterator {
func (b *Bitmap) Info() BitmapInfo {
info := BitmapInfo{
OpN: b.opN,
Containers: make([]ContainerInfo, 0, b.conts.Size()),
Containers: make([]ContainerInfo, 0, b.Containers.Size()),
}
citer, _ := b.conts.Iterator(0)
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
k, c := citer.Value()
ci := c.info()
@ -752,7 +747,7 @@ func (b *Bitmap) Check() error {
var a ErrorList
// Check each container.
citer, _ := b.conts.Iterator(0)
citer, _ := b.Containers.Iterator(0)
for citer.Next() {
k, c := citer.Value()
if err := c.check(); err != nil {
@ -816,7 +811,7 @@ func (itr *Iterator) Seek(seek uint64) {
itr.k = -1
// Move to the correct container.
itr.citer, _ = itr.bitmap.conts.Iterator(highbits(seek))
itr.citer, _ = itr.bitmap.Containers.Iterator(highbits(seek))
if !itr.citer.Next() {
itr.c = nil
return // eof
@ -3282,8 +3277,8 @@ func BitmapsEqual(b, c *Bitmap) error {
return errors.New("opNs not equal")
}
biter, _ := b.conts.Iterator(0)
citer, _ := c.conts.Iterator(0)
biter, _ := b.Containers.Iterator(0)
citer, _ := c.Containers.Iterator(0)
bn, cn := biter.Next(), citer.Next()
for ; bn && cn; bn, cn = biter.Next(), citer.Next() {
bk, bc := biter.Value()

38
roaring/roaring_internal_test.go
View file

@ -1782,7 +1782,7 @@ func TestDifferenceRunRun(t *testing.T) {
func TestWriteReadArray(t *testing.T) {
ca := &Container{array: []uint16{1, 10, 100, 1000}, n: 4, containerType: ContainerArray}
ba := NewBitmap()
ba.conts.Put(0, ca)
ba.Containers.Put(0, ca)
ba2 := NewBitmap()
var buf bytes.Buffer
_, err := ba.WriteTo(&buf)
@ -1793,8 +1793,8 @@ func TestWriteReadArray(t *testing.T) {
if err != nil {
t.Fatalf("error unmarshaling: %v", err)
}
if !reflect.DeepEqual(ba2.conts.Get(0).array, ca.array) {
t.Fatalf("array test expected %x, but got %x", ca.array, ba2.conts.Get(0).array)
if !reflect.DeepEqual(ba2.Containers.Get(0).array, ca.array) {
t.Fatalf("array test expected %x, but got %x", ca.array, ba2.Containers.Get(0).array)
}
}
@ -1805,7 +1805,7 @@ func TestWriteReadBitmap(t *testing.T) {
cb.bitmap[i] = 0x5555555555555555
}
bb := NewBitmap()
bb.conts.Put(0, cb)
bb.Containers.Put(0, cb)
bb2 := NewBitmap()
var buf bytes.Buffer
_, err := bb.WriteTo(&buf)
@ -1816,8 +1816,8 @@ func TestWriteReadBitmap(t *testing.T) {
if err != nil {
t.Fatalf("error unmarshaling: %v", err)
}
if !reflect.DeepEqual(bb2.conts.Get(0).bitmap, cb.bitmap) {
t.Fatalf("bitmap test expected %x, but got %x", cb.bitmap, bb2.conts.Get(0).bitmap)
if !reflect.DeepEqual(bb2.Containers.Get(0).bitmap, cb.bitmap) {
t.Fatalf("bitmap test expected %x, but got %x", cb.bitmap, bb2.Containers.Get(0).bitmap)
}
}
@ -1828,7 +1828,7 @@ func TestWriteReadFullBitmap(t *testing.T) {
cb.bitmap[i] = 0xffffffffffffffff
}
bb := NewBitmap()
bb.conts.Put(0, cb)
bb.Containers.Put(0, cb)
bb2 := NewBitmap()
var buf bytes.Buffer
_, err := bb.WriteTo(&buf)
@ -1839,22 +1839,22 @@ func TestWriteReadFullBitmap(t *testing.T) {
if err != nil {
t.Fatalf("error unmarshaling: %v", err)
}
if !reflect.DeepEqual(bb2.conts.Get(0).bitmap, cb.bitmap) {
t.Fatalf("bitmap test expected %x, but got %x", cb.bitmap, bb2.conts.Get(0).bitmap)
if !reflect.DeepEqual(bb2.Containers.Get(0).bitmap, cb.bitmap) {
t.Fatalf("bitmap test expected %x, but got %x", cb.bitmap, bb2.Containers.Get(0).bitmap)
}
if bb2.conts.Get(0).n != cb.n {
t.Fatalf("bitmap test expected count %x, but got %x", cb.n, bb2.conts.Get(0).n)
if bb2.Containers.Get(0).n != cb.n {
t.Fatalf("bitmap test expected count %x, but got %x", cb.n, bb2.Containers.Get(0).n)
}
if bb2.conts.Get(0).count() != cb.count() {
t.Fatalf("bitmap test expected count %x, but got %x", cb.n, bb2.conts.Get(0).n)
if bb2.Containers.Get(0).count() != cb.count() {
t.Fatalf("bitmap test expected count %x, but got %x", cb.n, bb2.Containers.Get(0).n)
}
}
func TestWriteReadRun(t *testing.T) {
cr := &Container{runs: []interval16{{start: 3, last: 13}, {start: 100, last: 109}}, n: 21, containerType: ContainerRun}
br := NewBitmap()
br.conts.Put(0, cr)
br.Containers.Put(0, cr)
br2 := NewBitmap()
var buf bytes.Buffer
_, err := br.WriteTo(&buf)
@ -1865,8 +1865,8 @@ func TestWriteReadRun(t *testing.T) {
if err != nil {
t.Fatalf("error unmarshaling: %v", err)
}
if !reflect.DeepEqual(br2.conts.Get(0).runs, cr.runs) {
t.Fatalf("run test expected %x, but got %x", cr.runs, br2.conts.Get(0).runs)
if !reflect.DeepEqual(br2.Containers.Get(0).runs, cr.runs) {
t.Fatalf("run test expected %x, but got %x", cr.runs, br2.Containers.Get(0).runs)
}
}
@ -2125,7 +2125,7 @@ func TestXorBitmapRun(t *testing.T) {
func TestIteratorArray(t *testing.T) {
// use values that span two containers
b := NewBitmap(0, 1, 10, 100, 1000, 10000, 90000, 100000)
if !b.conts.Get(0).isArray() {
if !b.Containers.Get(0).isArray() {
t.Fatalf("wrong container type")
}
@ -2178,7 +2178,7 @@ func TestIteratorBitmap(t *testing.T) {
for i := uint64(75000); i < 75100; i++ {
b.Add(i)
}
if !b.conts.Get(0).isBitmap() {
if !b.Containers.Get(0).isBitmap() {
t.Fatalf("wrong container type")
}
@ -2224,7 +2224,7 @@ func TestIteratorBitmap(t *testing.T) {
func TestIteratorRuns(t *testing.T) {
b := NewBitmap(0, 1, 2, 3, 4, 5, 1000, 1001, 1002, 1003, 1004, 1005, 100000, 100001, 100002, 100003, 100004, 100005)
b.Optimize()
if !b.conts.Get(0).isRun() {
if !b.Containers.Get(0).isRun() {
t.Fatalf("wrong container type")
}

13
server/enterprise.go Normal file
View file

@ -0,0 +1,13 @@
// +build enterprise
package server
import (
"github.com/pilosa/pilosa/enterprise/b"
"github.com/pilosa/pilosa/roaring"
)
func init() {
// Replace Bitmap constructor with B+Tree implementation
roaring.NewFileBitmap = b.NewBTreeBitmap
}