如此性子试问有几人能做到。详见JDKProxy官方文档。2.实现思路在学习了HashMap(#7)和LinkedHashMap(#8)后，是不是觉得这俩数据结构简直太适合做LRUCache了！那么动手实现一下：基于HashMap和双向链表的实现publicclassLRUCache{??classNode{????Nodepre;????Nodenext;????Integerkey;????Integerval;?????Node(Integerk,Integerv){??????key=k;??????val=v;????}??}???Mapmap=newHashMap();??//Thehead(eldest)ofthedoublylinkedlist.??Nodehead;??//Thetail(youngest)ofthedoublylinkedlist.??Nodetail;??intcap;??publicLRUCache(intcapacity){????cap=capacity;????head=newNode(null,null);????tail=newNode(null,null);????head.next=tail;????tail.pre=head;??}???publicintget(intkey){????Noden=map.get(key);????if(n!=null){??????n.pre.next=n.next;??????n.next.pre=n.pre;??????appendTail(n);??????returnn.val;????}????return-1;??}???publicvoidset(intkey,intvalue){????Noden=map.get(key);????//existed????if(n!=null){??????n.val=value;??????map.put(key,n);??????n.pre.next=n.next;??????n.next.pre=n.pre;??????appendTail(n);??????return;????}????//else{????if(map.size()==cap){??????Nodetmp=head.next;??????head.next=head.next.next;??????head.next.pre=head;??????map.remove(tmp.key);????}????n=newNode(key,value);????//youngestnodeappendtaill????appendTail(n);????map.put(key,n);??}???privatevoidappendTail(Noden){????n.next=tail;????n.pre=tail.pre;????tail.pre.next=n;????tail.pre=n;??}}基于LinkedHashMap的实现HashMap+双向链表？这不就是LinkedHashMap吗！publicclassLRUCache{???privateintcapacity;??privateMapcache;???publicLRUCache(intcapacity){????this.capacity=capacity;????this.cache=newjava.util.LinkedHashMap(capacity,0.75f,true){??????//定义put后的移除规则，大于容量就删除eldest??????protectedbooleanremoveEldestEntry(Map.Entryeldest){????????returnsize()>capacity;??????}????};??}???publicintget(intkey){????if(cache.containsKey(key)){??????returncache.get(key);????}else??????return-1;??}???publicvoidset(intkey,intvalue){????cache.put(key,value);??}}【今日微信公号推荐↓】更多推荐请看《值得关注的技术和设计公众号》其中推荐了包括技术、设计、极客和IT相亲相关的热门公众号。黄强说。