update(pkg): commit lru

pkg/lru/Lru.go

@@ -0,0 +1,89 @@
+package lru
+
+import (
+	"container/list"
+	"errors"
+	"gitee.com/timedb/wheatCache/pkg/structure"
+)
+
+type Node struct {
+	Key   interface{}
+	value structure.KeyBaseInterface
+}
+
+func (*Node) NewCacheNode(k interface{}, v structure.KeyBaseInterface) Node {
+	return Node{Key: k, value: v}
+}
+
+type LRUCache struct {
+	maxsize   int64 //最大的长度
+	clearsize int64 // 清理长度
+	nowsize   int64 // 现在的长度
+	li        *list.List
+	LruMap    map[interface{}]*list.Element
+}
+
+// NewLRUCache lru初始化
+func NewLRUCache(msize, csize int64) *LRUCache {
+	return &LRUCache{
+		maxsize:   msize,
+		clearsize: csize,
+		nowsize:   0,
+		li:        list.New(),
+		LruMap:    make(map[interface{}]*list.Element)}
+}
+
+// Add 增
+func (lru *LRUCache) Add(k interface{}, v structure.KeyBaseInterface) error {
+
+	if lru.li == nil {
+		return nil
+	}
+	if PreEle, ok := lru.LruMap[k]; ok {
+		lru.li.MoveToFront(PreEle)
+		PreEle.Value.(*Node).value = v
+		lru.nowsize += PreEle.Value.(*Node).value.SizeByte()
+		return nil
+	}
+	if lru.nowsize >= lru.maxsize*1/3 {
+		lru.nowsize -= lru.maxsize
+		if PreEle, ok := lru.LruMap[k]; ok {
+			cacheNode := PreEle.Value.(*Node).value
+			delete(lru.LruMap, cacheNode.SizeByte())
+			lru.li.Remove(PreEle)
+		}
+	}
+	newEle := lru.li.PushFront(&Node{k, v})
+	lru.LruMap[k] = newEle
+	return nil
+}
+
+// Get 查
+func (lru *LRUCache) Get(k interface{}) (v structure.KeyBaseInterface, ret bool) {
+
+	if lru.LruMap == nil {
+		return v, false
+	}
+	if PreEle, ok := lru.LruMap[k]; ok {
+		// 移到最前面
+		lru.li.MoveToFront(PreEle)
+		return PreEle.Value.(*Node).value, true
+	}
+	return v, false
+}
+
+// Clear 删除
+func (lru *LRUCache) Clear(k interface{}) error {
+	if lru.LruMap == nil {
+		return errors.New("cache 为空")
+	}
+	for lru.nowsize >= lru.clearsize*1/3 {
+		if PreEle, ok := lru.LruMap[k]; ok {
+			cacheNode := PreEle.Value.(*Node).value
+			delete(lru.LruMap, cacheNode.SizeByte())
+			lru.li.Remove(PreEle)
+			return nil
+		}
+	}
+	return nil
+}