java - Cache.asMap().put() 或 Cache.put()

Question

我正在使用 Google-guava-cache。将其定义为:

Cache<String, String> myCache= CacheBuilder.newBuilder().maximumSize(100).build();  

当我执行 map 操作(例如获取/放置)时，使用:

  myCache.asMap().put("someString", "someString");
  String someValueFromCache = myCache.asMap().get("someString");

我想知道如果我按照以下方式使用它，即不将其用作 map ，是否会有任何优化或任何类型的差异:

  myCache.put("someString", "someString");
  String someValueFromCache = myCache.get("someString");

Answer 1

来自 Guava 缓存文档:https://github.com/google/guava/wiki/CachesExplained#inserted-directly

Values may be inserted into the cache directly with cache.put(key, value). This overwrites any previous entry in the cache for the specified key. Changes can also be made to a cache using any of the ConcurrentMap methods exposed by the Cache.asMap() view. Note that no method on the asMap view will ever cause entries to be automatically loaded into the cache. Further, the atomic operations on that view operate outside the scope of automatic cache loading, so Cache.get(K, Callable) should always be preferred over Cache.asMap().putIfAbsent in caches which load values using either CacheLoader or Callable.

不要认为您应该使用 asMap() View 来修改缓存。