func NewTopKCounter(capacity int64) *TopKCounter {
return &TopKCounter{
capacity: capacity,
counterMap: make(map[string]*list.Element),
bucketList: list.New(),
}
}
func NewTopKCounterBytes(buf []byte) (c *TopKCounter, err error) {
defer func() {
if r := recover(); r != nil {
switch x := r.(type) {
case string:
err = errors.New(x)
case error:
err = x
default:
err = errors.New("Deserialization failed.")
}
c = nil
}
}()
capacity := int64(binary.LittleEndian.Uint64(buf))
bucketListLen := int(binary.LittleEndian.Uint64(buf[8:]))
p := 16
counterMap := make(map[string]*list.Element)
bucketList := list.New()
for i := 0; i < bucketListLen; i++ {
count := int64(binary.LittleEndian.Uint64(buf[p:]))
buck := newBucket(count)
listLen := int(binary.LittleEndian.Uint64(buf[p+8:]))
p += 16
buckElem := bucketList.PushBack(buck)
counterList := list.New()
buck.counterList = counterList
for j := 0; j < listLen; j++ {
ctr := &counter{}
ctr.count = int64(binary.LittleEndian.Uint64(buf[p:]))
ctr.error = int64(binary.LittleEndian.Uint64(buf[p+8:]))
itemLen := int(binary.LittleEndian.Uint64(buf[p+16:]))
p += 24
ctr.item = string(buf[p : p+itemLen])
p += itemLen
ctr.bucketNode = buckElem
ctrElem := counterList.PushBack(ctr)
counterMap[ctr.item] = ctrElem
}
}
return &TopKCounter{
capacity: capacity,
counterMap: counterMap,
bucketList: bucketList,
}, nil
}
func newBucket(count int64) *bucket {
return &bucket{
counterList: list.New(),
count: count,
}
}