移除键后，Guava Map Cache 会缩小吗

Question

private Cache<Object, String> cache = CacheBuilder.newBuilder()
        .concurrencyLevel(4)
        .expireAfterAccess(24, TimeUnit.HOURS)
        .initialCapacity(1024)
        .maximumSize(1_00_000)
        .build();
private ConcurrentMap<Object, String> cacheMap = cache.asMap();

这是我的代码，它很简单，只是创建一个 Guava 地图缓存。问题是，如果我从这张地图中删除（）键，GC 是否能够从这张地图中收回内存？不使用 weakReference（我没有存储嵌套对象，如 Set 或 Map 等...）？

Answer 1

是

来自 Guava's Cache.asMap javadoc（强调我的）：

Returns a view of the entries stored in this cache as a thread-safe map. Modifications made to the map directly affect the cache.

并且来自 Guava's Cache Explained wiki page：

At any time, you may explicitly invalidate cache entries rather than waiting for entries to be evicted.

您可能想要检查整个 wiki 页面而不是我突出显示的部分。

移除键后，Guava Map Cache 会缩小吗

will Guava Map Cache shrink when keys are removed

garbage-collection

guava

是