public class LocalMemory {
    private static Logger logger = LogManager.getLogger(LocalMemory.class);
    public static CacheData get(String key) {
        SoftReference<CacheData> cacheDataSoftReference = localData.get(key);
        CacheData cacheData = cacheDataSoftReference.get();
        return cacheData;
    }
    // 数据
    static class CacheData {
        // 过期时间
        private Long invalidTime;
        private Object data;
        public Long getInvalidTime() {
            return invalidTime;
        }
        public void setInvalidTime(Long invalidTime) {
            this.invalidTime = invalidTime;
        }
        public Object getData() {
            return data;
        }
        public void setData(Object data) {
            this.data = data;
        }
        @Override
        public String toString() {
            return "CacheData{" +
                    "invalidTime=" + invalidTime +
                    ", data=" + data +
                    '}';
        }
    }
    // 存储本地缓存数据.用软引用避免OutOfMemoryError
    static Map<String, SoftReference<CacheData>> localData = new ConcurrentHashMap<String, SoftReference<CacheData>>();
    public static final int MAX_SIZE = 10000;
    public static final int WARN_VALUE = 8000;
    /**
     * @param key     缓存KEY
     * @param value   缓存数据
     * @param timeOut 超时时间，单位秒
     */
    public static void put(String key, Object value, Long timeOut) {
        if (localData.size() >= WARN_VALUE) {
            logger.warn("注意:本地缓存已经达到临界值,size:" + localData.size());
        }
        if (localData.size() > MAX_SIZE) {
            logger.error("超出最大值:" + localData.size());
            return;
        }
        CacheData cacheData = new CacheData();
        long now = System.currentTimeMillis();
        long invalidTime = now + (timeOut * 1000);
        cacheData.setData(value);
        cacheData.setInvalidTime(invalidTime);
        SoftReference<CacheData> refCacheData = new SoftReference<CacheData>(cacheData);
        localData.put(key, refCacheData);
    }
    public static void main(String[] args) throws InterruptedException {
        String key = "test";
        Object value = "hello world";
        LocalMemory.put("test", value, 1l);
        System.out.println(LocalMemory.get(key));
        Thread.sleep(2000);
        System.out.println(LocalMemory.get(key));
    }
}