cache

Documentation

Overview

Package cache Package lru implements an LRU cache.

Index

• type Cache
  • func NewCache(size int) (c *Cache)
  • func (c *Cache) Add(key Key, value interface{})
  • func (c *Cache) Clear()
  • func (c *Cache) Contains(key interface{}) bool
  • func (c *Cache) Get(key interface{}) (value interface{}, ok bool)
  • func (c *Cache) Keys() []interface{}
  • func (c *Cache) Length() int
  • func (c *Cache) Remove(key interface{})
  • func (c *Cache) RemoveOldest()
• type Key
• type Lru
  • func New(maxEntries int) *Lru
  • func (c *Lru) Add(key Key, value interface{})
  • func (c *Lru) Clear()
  • func (c *Lru) Contains(key interface{}) (ok bool)
  • func (c *Lru) Get(key Key) (value interface{}, ok bool)
  • func (c *Lru) Keys() []interface{}
  • func (c *Lru) Len() int
  • func (c *Lru) Remove(key Key)
  • func (c *Lru) RemoveOldest()

Types

type Cache

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

Cache is a thread-safe fixed size LRU cache.

func NewCache

func NewCache(size int) (c *Cache)

NewCache creates an LRU of the given size.

func (*Cache) Add

func (c *Cache) Add(key Key, value interface{})

Add adds a value to the cache. Returns true if an eviction occurred.

func (*Cache) Clear

func (c *Cache) Clear()

Clear is used to completely clear the cache.

func (*Cache) Contains

func (c *Cache) Contains(key interface{}) bool

Contains checks if a key is in the cache, without updating the recent-ness or deleting it for being stale.

func (*Cache) Get

func (c *Cache) Get(key interface{}) (value interface{}, ok bool)

Get looks up a key's value from the cache.

func (*Cache) Keys

func (c *Cache) Keys() []interface{}

Keys returns a slice of the keys in the cache, from oldest to newest.

func (*Cache) Length

func (c *Cache) Length() int

Length returns the number of items in the cache.

func (*Cache) Remove

func (c *Cache) Remove(key interface{})

Remove removes the provided key from the cache.

func (*Cache) RemoveOldest

func (c *Cache) RemoveOldest()

RemoveOldest removes the oldest item from the cache.

type Key

type Key interface{}

A Key may be any value that is comparable. See http://golang.org/ref/spec#Comparison_operators

type Lru

type Lru struct {
	// MaxEntries is the maximum number of cache entries before
	// an item is evicted. Zero means no limit.
	MaxEntries int

	// OnEvicted optionally specifies a callback function to be
	// executed when an entry is purged from the cache.
	OnEvicted func(key Key, value interface{})
	// contains filtered or unexported fields
}

Lru is an LRU cache. It is not safe for concurrent access.

func New

func New(maxEntries int) *Lru

New creates a new Cache. If maxEntries is zero, the cache has no limit and it's assumed that eviction is done by the caller.

func (*Lru) Add

func (c *Lru) Add(key Key, value interface{})

Add adds a value to the cache.

func (*Lru) Clear

func (c *Lru) Clear()

Clear purges all stored items from the cache.

func (*Lru) Contains

func (c *Lru) Contains(key interface{}) (ok bool)

func (*Lru) Get

func (c *Lru) Get(key Key) (value interface{}, ok bool)

Get looks up a key's value from the cache.

func (*Lru) Keys

func (c *Lru) Keys() []interface{}

func (*Lru) Len

func (c *Lru) Len() int

Len returns the number of items in the cache.

func (*Lru) Remove

func (c *Lru) Remove(key Key)

Remove removes the provided key from the cache.

func (*Lru) RemoveOldest

func (c *Lru) RemoveOldest()

RemoveOldest removes the oldest item from the cache.