public Class NoOpCache

Create a NoOpCache instance with the specified name.

Parameters

name:String

the name of the cache

Implements org.springframework.cache.Cache.clear.

Doc from org.springframework.cache.Cache.clear.

Clear the cache through removing all mappings.

Actual clearing may be performed in an asynchronous or deferred fashion, with subsequent lookups possibly still seeing the entries. This may for example be the case with transactional cache decorators. Use invalidate() for guaranteed immediate removal of entries.

If the cache is supposed to be compatible with CompletableFuture and reactive interactions, the clear operation needs to be effectively non-blocking, with any backend write-through happening asynchronously. This goes along with a cache implemented and configured to support retrieve(Object) and retrieve(Object, Supplier).

Annotations

@Override

Implements org.springframework.cache.Cache.evict.

Doc from org.springframework.cache.Cache.evict.

Evict the mapping for this key from this cache if it is present.

Actual eviction may be performed in an asynchronous or deferred fashion, with subsequent lookups possibly still seeing the entry. This may for example be the case with transactional cache decorators. Use evictIfPresent for guaranteed immediate removal.

If the cache is supposed to be compatible with CompletableFuture and reactive interactions, the evict operation needs to be effectively non-blocking, with any backend write-through happening asynchronously. This goes along with a cache implemented and configured to support retrieve(Object) and retrieve(Object, Supplier).

Parameters

key:Object

the key whose mapping is to be removed from the cache

Annotations

@Override

Overrides default org.springframework.cache.Cache.evictIfPresent.

Doc from org.springframework.cache.Cache.evictIfPresent.

Evict the mapping for this key from this cache if it is present, expecting the key to be immediately invisible for subsequent lookups.

The default implementation delegates to evict(Object), returning false for not-determined prior presence of the key. Cache providers and in particular cache decorators are encouraged to perform immediate eviction if possible (e.g. in case of generally deferred cache operations within a transaction) and to reliably determine prior presence of the given key.

Parameters

key:Object

the key whose mapping is to be removed from the cache

Returns:boolean

true if the cache was known to have a mapping for this key before, false if it did not (or if prior presence could not be determined)

Annotations

@Override

Implements org.springframework.cache.Cache.get.

Doc from org.springframework.cache.Cache.get.

Return the value to which this cache maps the specified key.

Returns null if the cache contains no mapping for this key; otherwise, the cached value (which may be null itself) will be returned in a ValueWrapper.

Parameters

key:Object

the key whose associated value is to be returned

Returns:Cache.ValueWrapper

the value to which this cache maps the specified key, contained within a ValueWrapper which may also hold a cached null value. A straight null being returned means that the cache contains no mapping for this key.

Annotations

@Override

@Nullable

Implements org.springframework.cache.Cache.get.

Doc from org.springframework.cache.Cache.get.

Return the value to which this cache maps the specified key, generically specifying a type that return value will be cast to.

Parameters

key:Object

the key whose associated value is to be returned

type:Class<T>

the required type of the returned value (may be null to bypass a type check; in case of a null value found in the cache, the specified type is irrelevant)

Returns:T

the value to which this cache maps the specified key (which may be null itself), or also null if the cache contains no mapping for this key

Annotations

@Override

@Nullable

Implements org.springframework.cache.Cache.get.

Doc from org.springframework.cache.Cache.get.

Return the value to which this cache maps the specified key, obtaining that value from valueLoader if necessary. This method provides a simple substitute for the conventional "if cached, return; otherwise create, cache and return" pattern.

If possible, implementations should ensure that the loading operation is synchronized so that the specified valueLoader is only called once in case of concurrent access on the same key.

If the valueLoader throws an exception, it is wrapped in a ValueRetrievalException

Parameters

key:Object

the key whose associated value is to be returned

Returns:T

the value to which this cache maps the specified key

Annotations

@Override

@Nullable

Implements org.springframework.cache.Cache.getName.

Doc from org.springframework.cache.Cache.getName.

Return the cache name.

Annotations

@Override

Implements org.springframework.cache.Cache.getNativeCache.

Doc from org.springframework.cache.Cache.getNativeCache.

Return the underlying native cache provider.

Annotations

@Override

Overrides default org.springframework.cache.Cache.invalidate.

Doc from org.springframework.cache.Cache.invalidate.

Invalidate the cache through removing all mappings, expecting all entries to be immediately invisible for subsequent lookups.

Returns:boolean

true if the cache was known to have mappings before, false if it did not (or if prior presence of entries could not be determined)

Annotations

@Override

Implements org.springframework.cache.Cache.put.

Doc from org.springframework.cache.Cache.put.

Associate the specified value with the specified key in this cache.

If the cache previously contained a mapping for this key, the old value is replaced by the specified value.

Actual registration may be performed in an asynchronous or deferred fashion, with subsequent lookups possibly not seeing the entry yet. This may for example be the case with transactional cache decorators. Use putIfAbsent for guaranteed immediate registration.

If the cache is supposed to be compatible with CompletableFuture and reactive interactions, the put operation needs to be effectively non-blocking, with any backend write-through happening asynchronously. This goes along with a cache implemented and configured to support retrieve(Object) and retrieve(Object, Supplier).

Parameters

key:Object

the key with which the specified value is to be associated

value:Object

the value to be associated with the specified key

Annotations

@Override

Overrides default org.springframework.cache.Cache.putIfAbsent.

Doc from org.springframework.cache.Cache.putIfAbsent.

Atomically associate the specified value with the specified key in this cache if it is not set already.

This is equivalent to:

ValueWrapper existingValue = cache.get(key);
if (existingValue == null) {
    cache.put(key, value);
}
return existingValue;

The default implementation delegates to get(Object) and put(Object, Object) along the lines of the code snippet above.

Parameters

key:Object

the key with which the specified value is to be associated

value:Object

the value to be associated with the specified key

Returns:Cache.ValueWrapper

the value to which this cache maps the specified key (which may be null itself), or also null if the cache did not contain any mapping for that key prior to this call. Returning null is therefore an indicator that the given value has been associated with the key.

Annotations

@Override

@Nullable

Overrides default org.springframework.cache.Cache.retrieve.

Doc from org.springframework.cache.Cache.retrieve.

Return the value to which this cache maps the specified key, wrapped in a CompletableFuture. This operation must not block but is allowed to return a completed CompletableFuture if the corresponding value is immediately available.

Can return null if the cache can immediately determine that it contains no mapping for this key (e.g. through an in-memory key map). Otherwise, the cached value will be returned in the CompletableFuture, with null indicating a late-determined cache miss. A nested ValueWrapper potentially indicates a nullable cached value; the cached value may also be represented as a plain element if null values are not supported. Calling code needs to be prepared to handle all those variants of the result returned by this method.

Parameters

key:Object

the key whose associated value is to be returned

Returns:CompletableFuture<?>

the value to which this cache maps the specified key, contained within a CompletableFuture which may also be empty when a cache miss has been late-determined. A straight null being returned means that the cache immediately determined that it contains no mapping for this key. A ValueWrapper contained within the CompletableFuture indicates a cached value that is potentially null; this is sensible in a late-determined scenario where a regular CompletableFuture-contained null indicates a cache miss. However, a cache may also return a plain value if it does not support the actual caching of null values, avoiding the extra level of value wrapping. Spring's cache processing can deal with all such implementation strategies.

Annotations

@Override

@Nullable

Overrides default org.springframework.cache.Cache.retrieve.

Doc from org.springframework.cache.Cache.retrieve.

Return the value to which this cache maps the specified key, obtaining that value from valueLoader if necessary. This method provides a simple substitute for the conventional "if cached, return; otherwise create, cache and return" pattern, based on CompletableFuture. This operation must not block.

If possible, implementations should ensure that the loading operation is synchronized so that the specified valueLoader is only called once in case of concurrent access on the same key.

Null values always indicate a user-level null value with this method. The provided CompletableFuture handle produces a value or raises an exception. If the valueLoader raises an exception, it will be propagated to the returned CompletableFuture handle.

Parameters

key:Object

the key whose associated value is to be returned

Returns:CompletableFuture<T>

the value to which this cache maps the specified key, contained within a CompletableFuture which will never be null. The provided future is expected to produce a value or raise an exception.

Annotations

@Override