README
¶
hashmap
Overview
A Golang lock-free thread-safe HashMap optimized for fastest read access.
Which changes?
I need types for my project, and golang has generics, why not? Maybe it has problems, I don't know, I'm new to golang :D
Usage
Set a value for a key in the map:
type Domain struct {
Hostname string
}
m := &HashMap[Domain]{}
m.Set("my", Domain{
Hostname: "google.com",
})
Read a value for a key from the map:
val, ok := m.Get("my")
if ok {
fmt.Println(val.Hostname)
}
Documentation
¶
Index ¶
- Constants
- type HashMap
- func (m *HashMap[T]) Cas(key, from, to T) bool
- func (m *HashMap[T]) CasHashedKey(hashedKey uintptr, from, to T) bool
- func (m *HashMap[T]) Del(key interface{})
- func (m *HashMap[T]) DelHashedKey(hashedKey uintptr)
- func (m *HashMap[T]) Fillrate() uintptr
- func (m *HashMap[T]) Get(key interface{}) (value T, ok bool)
- func (m *HashMap[T]) GetHashedKey(hashedKey uintptr) (value T, ok bool)
- func (m *HashMap[T]) GetOrInsert(key interface{}, value T) (actual T, loaded bool)
- func (m *HashMap[T]) GetStringKey(key string) (value T, ok bool)
- func (m *HashMap[T]) GetUintKey(key uintptr) (value T, ok bool)
- func (m *HashMap[T]) Grow(newSize uintptr)
- func (m *HashMap[T]) Insert(key interface{}, value T) bool
- func (m *HashMap[T]) Iter() <-chan KeyValue
- func (m *HashMap[T]) Len() int
- func (m *HashMap[T]) Set(key interface{}, value T)
- func (m *HashMap[T]) SetHashedKey(hashedKey uintptr, value T)
- func (m *HashMap[T]) String() string
- type KeyValue
- type List
- func (l *List) Add(element *ListElement, searchStart *ListElement) (existed bool, inserted bool)
- func (l *List) AddOrUpdate(element *ListElement, searchStart *ListElement) bool
- func (l *List) Cas(element *ListElement, oldValue interface{}, searchStart *ListElement) bool
- func (l *List) Delete(element *ListElement)
- func (l *List) First() *ListElement
- func (l *List) Head() *ListElement
- func (l *List) Len() int
- type ListElement
Constants ¶
const DefaultSize = 8
DefaultSize is the default size for a zero allocated map
const MaxFillRate = 50
MaxFillRate is the maximum fill rate for the slice before a resize will happen.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type HashMap ¶
type HashMap[T any] struct { // contains filtered or unexported fields }
HashMap implements a read optimized hash map.
func (*HashMap[T]) Cas ¶
Cas performs a compare and swap operation sets the value under the specified hash key to the map. An existing item for this key will be overwritten.
func (*HashMap[T]) CasHashedKey ¶
CasHashedKey performs a compare and swap operation sets the value under the specified hash key to the map. An existing item for this key will be overwritten.
func (*HashMap[T]) Del ¶
func (m *HashMap[T]) Del(key interface{})
Del deletes the key from the map.
func (*HashMap[T]) DelHashedKey ¶
DelHashedKey deletes the hashed key from the map.
func (*HashMap[T]) Get ¶
Get retrieves an element from the map under given hash key. Using interface{} adds a performance penalty. Please consider using GetUintKey or GetStringKey instead.
func (*HashMap[T]) GetHashedKey ¶
GetHashedKey retrieves an element from the map under given hashed key.
func (*HashMap[T]) GetOrInsert ¶
GetOrInsert returns the existing value for the key if present. Otherwise, it stores and returns the given value. The loaded result is true if the value was loaded, false if stored.
func (*HashMap[T]) GetStringKey ¶
GetStringKey retrieves an element from the map under given string key.
func (*HashMap[T]) GetUintKey ¶
GetUintKey retrieves an element from the map under given integer key.
func (*HashMap[T]) Grow ¶
Grow resizes the hashmap to a new size, gets rounded up to next power of 2. To double the size of the hashmap use newSize 0. This function returns immediately, the resize operation is done in a goroutine. No resizing is done in case of another resize operation already being in progress.
func (*HashMap[T]) Insert ¶
Insert sets the value under the specified key to the map if it does not exist yet. If a resizing operation is happening concurrently while calling Set, the item might show up in the map only after the resize operation is finished. Returns true if the item was inserted or false if it existed.
func (*HashMap[T]) Iter ¶
func (m *HashMap[T]) Iter() <-chan KeyValue
Iter returns an iterator which could be used in a for range loop. The order of the items is sorted by hash keys.
func (*HashMap[T]) Set ¶
func (m *HashMap[T]) Set(key interface{}, value T)
Set sets the value under the specified key to the map. An existing item for this key will be overwritten. If a resizing operation is happening concurrently while calling Set, the item might show up in the map only after the resize operation is finished.
func (*HashMap[T]) SetHashedKey ¶
SetHashedKey sets the value under the specified hash key to the map. An existing item for this key will be overwritten. You can use this function if your keys are already hashes and you want to avoid another hashing of the key. Do not use non hashes as keys for this function, the performance would decrease! If a resizing operation is happening concurrently while calling Set, the item might show up in the map only after the resize operation is finished.
type KeyValue ¶
type KeyValue struct {
Key interface{}
Value interface{}
}
KeyValue represents a key/value that is returned by the iterator.
type List ¶
type List struct {
// contains filtered or unexported fields
}
List is a sorted doubly linked list.
func (*List) Add ¶
func (l *List) Add(element *ListElement, searchStart *ListElement) (existed bool, inserted bool)
Add adds an item to the list and returns false if an item for the hash existed. searchStart = nil will start to search at the head item
func (*List) AddOrUpdate ¶
func (l *List) AddOrUpdate(element *ListElement, searchStart *ListElement) bool
AddOrUpdate adds or updates an item to the list.
func (*List) Cas ¶
func (l *List) Cas(element *ListElement, oldValue interface{}, searchStart *ListElement) bool
Cas compares and swaps the value of an item in the list.
func (*List) Delete ¶
func (l *List) Delete(element *ListElement)
Delete deletes an element from the list.
type ListElement ¶
type ListElement struct {
// contains filtered or unexported fields
}
ListElement is an element of a list.
func (*ListElement) Next ¶
func (e *ListElement) Next() *ListElement
Next returns the item on the right.
func (*ListElement) Previous ¶
func (e *ListElement) Previous() *ListElement
Previous returns the item on the left.
func (*ListElement) Value ¶
func (e *ListElement) Value() (value interface{})
Value returns the value of the list item.
Source Files