Java – LRU caching using LinkedHashMap

I try to use LinkedHashMap to implement LRU caching

Note that if you re insert the key into the map, the insertion order is not affected

But when I make the following expression

public class LRUCache<K,V> extends LinkedHashMap<K,V> {
    private int size;

    public static void main(String[] args) {
        LRUCache<Integer,Integer> cache = LRUCache.newInstance(2);
        cache.put(1,1);
        cache.put(2,2);
        cache.put(1,1);
        cache.put(3,3);

        System.out.println(cache);
    }

    private LRUCache(int size) {
        super(size,0.75f,true);
        this.size = size;
    }

    @Override
    protected boolean removeEldestEntry(Map.Entry<K,V> eldest) {
        return size() > size;
    }

    public static <K,V> LRUCache<K,V> newInstance(int size) {
        return new LRUCache<K,V>(size);
    }

}

Output is

{1=1,3=3}

This indicates that reinsertion does affect the order Does anyone know any explanation?

Solution

As @ Jeffrey said, you are using accessorder When creating a LinkedHashMap, the third parameter specifies how the order changes

"true for access-order,false for insertion-order"

For a more detailed implementation of LRU, you can take a look at this http://www.programcreek.com/2013/03/leetcode-lru-cache-java/