Support for custom cache registration in CaffeineCacheManager

[T3rm1]

Affects: 5.2.6

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It is quite common to have multiple caches with different value lifetime. Right now CaffeineCacheManager creates every Cache with the default settings or the settings set through either of setCacheLoader, setCacheSpecification or setCaffeineSpec. But those settings apply to all Caches.
If cacheMap would be exposed (maybe just a simple getter) it would be possible to add prebuilt caches with custom settings to it.

[jhoeller]

I suppose we could alternatively introduce dedicated registration methods for individual caches, e.g. taking cache name plus cache specification, or potentially taking a callback for creating the native cache instance... I'd rather make the use case first-class than expose the inner map here, e.g.: registerCache(String name, com.github.benmanes.caffeine.cache.Cache cache)

If you'd like full control of individual caches, you could also use SimpleCacheManager and populate it with a collection of CaffeineCache instances of your choice.

[T3rm1]

I like the idea with registerCache(String name, com.github.benmanes.caffeine.cache.Cache cache) which then puts the cache into the map. I think it is better than the callback approach.

[jhoeller]

I've just implemented such a registerCustomCache method, the only hurdle having been that setCaffeineSpec etc calls on the CaffeineCacheManager should only reinitialize default caches but not such custom cache registrations (that's also the reason for the registerCustomCache naming). In any case, it seems to flow nicely with any kind of Caffeine.newBuilder() or Caffeine.from(...) usage.

Alright, I'll roll this into 5.2.8 right away if this matches your use case as well :-)

[T3rm1]

Awesome! Thanks for doing this so fast. 🍺

[Praveen1027]

Hi. Is there a way I can get the generics in place while attempting to registerCustomCache(spring), something like :
Cache<String, String> cityCache = Caffeine.newBuilder() .expireAfterWrite(1, TimeUnit.DAYS).maximumSize(1000).build(); caffeineCacheManager.registerCustomCache("city_data", cityCache);// this fails