Java LRU的实现

最近在leetcode上做题的时，看到了一道有关LRU Cache的题目，正好我当初面试阿里巴巴的时候问到的。主要采用linkedHashMap来实现。

package edu.test.algorithm;

import java.util.LinkedHashMap;

public class LRUCache {
    LinkedHashMap<Integer,Integer> linkedHashMap;
    int capacity;
    public LRUCache(int capacity) {
        linkedHashMap=new LinkedHashMap<Integer, Integer>(capacity);
        this.capacity=capacity;
    }

    public int get(int key) {

            if(linkedHashMap.containsKey(key)){
                int value=linkedHashMap.get(key);
                linkedHashMap.remove(key);
                linkedHashMap.put(key, value);
                return value;
            }
            return -1;

    }

    public void set(int key, int value) {
              if(linkedHashMap.containsKey(key)){
                     linkedHashMap.remove(key);
                 }
                 else if(linkedHashMap.size()>=capacity){

                          linkedHashMap.remove(linkedHashMap.keySet().iterator().next());
                  }
                  linkedHashMap.put(key, value);

    }

}