ConcurrentLinkedHashMap

最近发现了一个好东西，基于LRU策略的缓存，说白了就是热点数据缓存；public class ConcurrentLinkedHashMapTest {

public class ConcurrentLinkedHashmapTest {
    public static void main(String[] args) {
        test01();
    }


    public static void test01() {
        ConcurrentLinkedHashMap<Long, String> map = new ConcurrentLinkedHashMap.Builder<Long, String>()
                .maximumWeightedCapacity(2).weigher(Weighers.singleton()).build();
        map.put(01L, "hello");
        map.put(02L, "zl");
        System.out.println(map.get(01L));
        map.put(03L, "test");

        System.out.println(map.get(02L));
        System.out.println("over");
    }
}

　输出：hello  null   over

设置集合大小，以及数据权重，超过集合大小会去掉最早添加且没用到的数据；

public class ConcurrentLinkedHashmapTest {
    public static void main(String[] args) {
        test01();
    }


    public static void test01() {
        ConcurrentLinkedHashMap<Long, String> map = new ConcurrentLinkedHashMap.Builder<Long, String>()
                .maximumWeightedCapacity(2).weigher(Weighers.singleton()).build();
        map.put(01L, "hello");
        map.put(02L, "zl");
        map.put(03L, "test");
        System.out.println(map.get(01L));
        System.out.println("over");
    }
}

　　输出：null over