用java的LinkedHashMap实现LRU

package LRU; import java.util.*; /** * LRU class * * @author wsy * @Date 2020/10/20 18:50 */ public class LRU extends LinkedHashMap { private static float LOAD_FACTOR = 0.75f; private static int INIT_CAPACITY = 3; private float maxCapacity; public LRU(int maxCapacity){ super(INIT_CAPACITY,LOAD_FACTOR,true); this.maxCapacity = maxCapacity; } @Override /** * 如果当前该函数返回true，表示应该删除EldestEntry。否则不删，继续扩容。 */ protected boolean removeEldestEntry(Map.Entry eldest) { if (size() > maxCapacity){ return true; } return false; } public static void main(String[] args) { LRU cache = new LRU(3); cache.put(1,null); cache.put(2,null); cache.put(3,null); cache.put(1,null); cache.put(4,null); for (Object object: cache.entrySet()) { System.out.println(object);//3 1 4 } } }