Guava Cache本地缓存

public class CacheProTest {
    LoadingCache<Long, Person> cache;
    private int cacheTimeoutSeconds = 10; // 10秒

    Integer counter = 1;

    @Before
    public void initialize() {
        System.out.println("初始化");

        cache = CacheBuilder.newBuilder()
                        /* 回收策略：基于容量（least-recently-used eviction when a maximum size is exceeded） */
                        .maximumSize(10) 
                        // .initialCapacity(initialCapacity)
                        
                        /* 回收策略：基于存活时间（time-based expiration of entries, measured since last access or last write） */
                        .expireAfterWrite(cacheTimeoutSeconds, TimeUnit.SECONDS)
                        // .expireAfterAccess(duration, unit)
                        // .refreshAfterWrite(duration, unit)
                        
                        /* 回收策略：基于权重 */
                        // .maximumWeight(maximumWeight)
                        // .weigher(weigher)

                        /* 回收策略：基于引用（keys automatically wrapped in weak references, values automatically wrapped in weak or soft references）*/
                        // .weakKeys()
                        // .weakValues()
                        // .softValues()
                        
                        // 设置并发数为5，即同一时间最多只能有5个线程往cache执行写入操作
                        // .concurrencyLevel(concurrencyLevel)

                        /* 缓存访问统计（accumulation of cache access statistics） */
                        .recordStats()
                        
                        /* 移除监听器（notification of evicted (or otherwise removed) entries） */
                        // .removalListener(listener)

                        .build(new CacheLoader<Long, Person>() {

                            /* 自动加载（automatic loading of entries into the cache） */
                            @Override
                            public Person load(Long id) throws Exception {
                                System.out.println("获取值, id=" + id);

                                // 调用接口获取值
                                Person p = new Person();
                                p.setId(id);
                                p.setName("name" + counter.toString());
                                counter++;

                                return p;
                            }
                        });
    }

    @Test
    public void test1() {
        try {
            /* 获值 */
            // ConcurrentMap<Long, Person> asMap = cache.asMap();

            // cache.get(key); //
            // cache.getAll(keys);

            // cache.getIfPresent(key);
            // cache.getAllPresent(keys);

            // cache.size();

            /* 存值 */
            // cache.put(key, value);
            // cache.putAll(m); // Map<? extends K, ? extends V> m

            /* 移除/删除 */
            // cache.refresh(key);
            // cache.invalidate(key);
            // cache.invalidateAll();
            // cache.invalidateAll(keys);
            // cache.cleanUp();

            /* 缓存访问统计 */
            CacheStats stats = cache.stats();
            stats.averageLoadPenalty();
            stats.evictionCount();
            stats.hitCount();
            stats.hitRate();
            stats.loadCount();
            stats.loadExceptionCount();
            stats.loadExceptionRate();
            stats.loadSuccessCount();
            stats.missCount();
            stats.missRate();
            stats.requestCount();
            stats.totalLoadTime();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }


    @Test
    public void test2() {
        try {
            Long id = 1L;
            Person person1 = cache.get(id);

            Thread.sleep(3L * 1000L);
            Person person2 = cache.get(id);

            Thread.sleep(11L * 1000L);
            Person person3 = cache.get(id);

            System.out.println(person1);
            System.out.println(person2);
            System.out.println(person3);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

class Person implements Serializable {
    private static final long serialVersionUID = 1L;

    private Long id;

    private String name;

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return JSON.toJSONString(this);
    }
}