const (
dicthtDefaultSize rune = 1 << 6
dicthtDefaultSizeMask = dicthtDefaultSize - 1
)
//节点用双链表
type DictEntry struct {
Key string
Val interface{}
Pre *DictEntry
Next *DictEntry
}
type Dictht struct {
Table map[rune]*DictEntry //节点map
Size rune //桶大小
SizeMask rune //掩码
Used int //已使用空间
}
type Dict struct {
Ht [2]*Dictht //1，2号dict
Rehashdx int //rehash signal
}
func NewTable() *Dict {
size := dicthtDefaultSize
ht1 := &Dictht{
Table: make(map[rune]*DictEntry, size),
Size: size,
SizeMask: dicthtDefaultSizeMask,
Used: 0,
}
ht2 := ht1
return &Dict{
Ht: [2]*Dictht{ht1, ht2},
Rehashdx: 0,
}
}
func (dict *Dict) Put(key string, value interface{}) {
if dict.Rehashdx == 0 {
//use dict[0] as main operation
dict.Ht[0].Put(key, value)
}
}
func (dict *Dict) Get(key string) interface{} {
if dict.Rehashdx == 0 {
//use dict[0] as main operation
return dict.Ht[0].Get(key)
}
return nil
}
func (dictht *Dictht) Get(key string) interface{} {
//get data from bucket
entry := &DictEntry{
Key: key,
Pre: nil,
Next: nil,
}
if item, ok := dictht.Table[dictht.GetDicthtIndex(key)]; ok {
if getEntry, ok := item.FindDictEntry(entry); ok {
return getEntry.Val
}
}
return nil
}
func (dictht *Dictht) Put(key string, value interface{}) {
//find bucket
entry := &DictEntry{
Key: key,
Val: value,
Pre: nil,
Next: nil,
}
if item, ok := dictht.Table[dictht.GetDicthtIndex(key)]; ok {
if _, ok := item.FindDictEntry(entry); ok {
item.AddDictEntry(entry)
}
} else {
dictht.Table[dictht.GetDicthtIndex(key)] = entry
dictht.Table[dictht.GetDicthtIndex(key)].AddDictEntry(entry)
}
}
func (entry *DictEntry) AddDictEntry(dictEntry *DictEntry) {
head := entry
if head == nil {
entry = dictEntry
return
}
for head.Next != nil {
head = head.Next
}
head.Next = dictEntry
dictEntry.Pre = head
return
}
func (entry *DictEntry) FindDictEntry(dictEntry *DictEntry) (*DictEntry, bool) {
head := entry
if head == nil {
return nil, false
}
for head.Next != nil {
if head.Key == dictEntry.Key {
return head, true
}
head = head.Next
}
return nil, false
}
//print dict data
func (dict *Dict) Print() {
}
/*func (table *HashTable) Get(key int) *Node {
}
func (table *HashTable) Delete(node *Node) {
}
func (table *HashTable) Increase(size int) {
}*/
//time33 hash function
func (dictht *Dictht) GetDicthtIndex(key string) rune {
hash := int32(5381)
kLen := len([]byte(key))
for i := 0; i < kLen; i++ {
hash = 1<<5 + 1 + int32([]byte(key)[i])
}
return hash & dictht.SizeMask
}
func main() {
table := internal.NewTable()
table.Put("hello", "world")
table.Put("3243", "34321321")
table.Put("hello2", "3433")
fmt.Println(table.Get("hello2"))
}
