标签:ESS exce span new ISE from head tween color
完整基于 Java 的代码参考如下 class DLinkedNode { String key; int value; DLinkedNode pre; DLinkedNode post; } LRU Cache public class LRUCache { private Hashtable<Integer, DLinkedNode> cache = new Hashtable<Integer, DLinkedNode>(); private int count; private int capacity; private DLinkedNode head, tail; public LRUCache(int capacity) { this.count = 0; this.capacity = capacity; head = new DLinkedNode(); head.pre = null; tail = new DLinkedNode(); tail.post = null; head.post = tail; tail.pre = head; } public int get(String key) { DLinkedNode node = cache.get(key); if(node == null){ return -1; // should raise exception here. } // move the accessed node to the head; this.moveToHead(node); return node.value; } public void set(String key, int value) { DLinkedNode node = cache.get(key); if(node == null){ DLinkedNode newNode = new DLinkedNode(); newNode.key = key; newNode.value = value; this.cache.put(key, newNode); this.addNode(newNode); ++count; if(count > capacity){ // pop the tail DLinkedNode tail = this.popTail(); this.cache.remove(tail.key); --count; } }else{ // update the value. node.value = value; this.moveToHead(node); } } /** * Always add the new node right after head; */ private void addNode(DLinkedNode node){ node.pre = head; node.post = head.post; head.post.pre = node; head.post = node; } /** * Remove an existing node from the linked list. */ private void removeNode(DLinkedNode node){ DLinkedNode pre = node.pre; DLinkedNode post = node.post; pre.post = post; post.pre = pre; } /** * Move certain node in between to the head. */ private void moveToHead(DLinkedNode node){ this.removeNode(node); this.addNode(node); } // pop the current tail. private DLinkedNode popTail(){ DLinkedNode res = tail.pre; this.removeNode(res); return res; } }
标签:ESS exce span new ISE from head tween color
原文地址:https://www.cnblogs.com/twoheads/p/11706261.html