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author | Christopher Speller <crspeller@gmail.com> | 2016-05-12 15:08:58 -0400 |
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committer | Christopher Speller <crspeller@gmail.com> | 2016-05-12 16:37:29 -0400 |
commit | 84d2482ddbff9564c9ad75b2d30af66e3ddfd44d (patch) | |
tree | 8bfa567d2b6381f4a996ada2deff8a16aa85a3ac /Godeps/_workspace/src/github.com/golang/groupcache/lru/lru.go | |
parent | d1efb66ad7b017f0fbfe6f0c20843b30f396e504 (diff) | |
download | chat-84d2482ddbff9564c9ad75b2d30af66e3ddfd44d.tar.gz chat-84d2482ddbff9564c9ad75b2d30af66e3ddfd44d.tar.bz2 chat-84d2482ddbff9564c9ad75b2d30af66e3ddfd44d.zip |
Updating go depencancies. Switching to go1.6 vendoring (#2949)
Diffstat (limited to 'Godeps/_workspace/src/github.com/golang/groupcache/lru/lru.go')
-rw-r--r-- | Godeps/_workspace/src/github.com/golang/groupcache/lru/lru.go | 121 |
1 files changed, 0 insertions, 121 deletions
diff --git a/Godeps/_workspace/src/github.com/golang/groupcache/lru/lru.go b/Godeps/_workspace/src/github.com/golang/groupcache/lru/lru.go deleted file mode 100644 index cdfe2991f..000000000 --- a/Godeps/_workspace/src/github.com/golang/groupcache/lru/lru.go +++ /dev/null @@ -1,121 +0,0 @@ -/* -Copyright 2013 Google Inc. - -Licensed under the Apache License, Version 2.0 (the "License"); -you may not use this file except in compliance with the License. -You may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 - -Unless required by applicable law or agreed to in writing, software -distributed under the License is distributed on an "AS IS" BASIS, -WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -See the License for the specific language governing permissions and -limitations under the License. -*/ - -// Package lru implements an LRU cache. -package lru - -import "container/list" - -// Cache is an LRU cache. It is not safe for concurrent access. -type Cache struct { - // MaxEntries is the maximum number of cache entries before - // an item is evicted. Zero means no limit. - MaxEntries int - - // OnEvicted optionally specificies a callback function to be - // executed when an entry is purged from the cache. - OnEvicted func(key Key, value interface{}) - - ll *list.List - cache map[interface{}]*list.Element -} - -// A Key may be any value that is comparable. See http://golang.org/ref/spec#Comparison_operators -type Key interface{} - -type entry struct { - key Key - value interface{} -} - -// 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 New(maxEntries int) *Cache { - return &Cache{ - MaxEntries: maxEntries, - ll: list.New(), - cache: make(map[interface{}]*list.Element), - } -} - -// Add adds a value to the cache. -func (c *Cache) Add(key Key, value interface{}) { - if c.cache == nil { - c.cache = make(map[interface{}]*list.Element) - c.ll = list.New() - } - if ee, ok := c.cache[key]; ok { - c.ll.MoveToFront(ee) - ee.Value.(*entry).value = value - return - } - ele := c.ll.PushFront(&entry{key, value}) - c.cache[key] = ele - if c.MaxEntries != 0 && c.ll.Len() > c.MaxEntries { - c.RemoveOldest() - } -} - -// Get looks up a key's value from the cache. -func (c *Cache) Get(key Key) (value interface{}, ok bool) { - if c.cache == nil { - return - } - if ele, hit := c.cache[key]; hit { - c.ll.MoveToFront(ele) - return ele.Value.(*entry).value, true - } - return -} - -// Remove removes the provided key from the cache. -func (c *Cache) Remove(key Key) { - if c.cache == nil { - return - } - if ele, hit := c.cache[key]; hit { - c.removeElement(ele) - } -} - -// RemoveOldest removes the oldest item from the cache. -func (c *Cache) RemoveOldest() { - if c.cache == nil { - return - } - ele := c.ll.Back() - if ele != nil { - c.removeElement(ele) - } -} - -func (c *Cache) removeElement(e *list.Element) { - c.ll.Remove(e) - kv := e.Value.(*entry) - delete(c.cache, kv.key) - if c.OnEvicted != nil { - c.OnEvicted(kv.key, kv.value) - } -} - -// Len returns the number of items in the cache. -func (c *Cache) Len() int { - if c.cache == nil { - return 0 - } - return c.ll.Len() -} |