@Target(value={TYPE,METHOD}) @Retention(value=RUNTIME) @Inherited @Documented public @interface Cacheable
Each time an advised method is invoked, caching behavior will be applied,
checking whether the method has been already invoked for the given arguments.
A sensible default simply uses the method parameters to compute the key, but
a SpEL expression can be provided via the key()
attribute, or a custom
KeyGenerator
implementation can
replace the default one (see keyGenerator()
).
If no value is found in the cache for the computed key, the target method
will be invoked and the returned value will be stored in the associated cache.
Note that Optional
return types are unwrapped automatically.
If an Optional
value is present, it will be stored in the associated cache. If an Optional
value is not present, null
will be stored in the associated cache.
This annotation may be used as a meta-annotation to create custom composed annotations with attribute overrides.
CacheConfig
Modifier and Type | Optional Element and Description |
---|---|
String |
cacheManager
The bean name of the custom
CacheManager to use to
create a default CacheResolver if none
is set already. |
String[] |
cacheNames
Names of the caches in which method invocation results are stored.
|
String |
cacheResolver
The bean name of the custom
CacheResolver
to use. |
String |
condition
Spring Expression Language (SpEL) expression used for making the method
caching conditional.
|
String |
key
Spring Expression Language (SpEL) expression for computing the key dynamically.
|
String |
keyGenerator
The bean name of the custom
KeyGenerator
to use. |
boolean |
sync
Synchronize the invocation of the underlying method if several threads are
attempting to load a value for the same key.
|
String |
unless
Spring Expression Language (SpEL) expression used to veto method caching.
|
String[] |
value
Alias for
cacheNames() . |
@AliasFor(value="cacheNames") public abstract String[] value
cacheNames()
.@AliasFor(value="value") public abstract String[] cacheNames
Names may be used to determine the target cache (or caches), matching the qualifier value or bean name of a specific bean definition.
value()
,
CacheConfig.cacheNames()
public abstract String key
Default is ""
, meaning all method parameters are considered as a key,
unless a custom keyGenerator()
has been configured.
The SpEL expression evaluates against a dedicated context that provides the following meta-data:
#root.method
, #root.target
, and #root.caches
for
references to the method
, target object, and
affected cache(s) respectively.#root.methodName
) and target class
(#root.targetClass
) are also available.
#root.args[1]
, #p1
or #a1
. Arguments
can also be accessed by name if that information is available.public abstract String keyGenerator
KeyGenerator
to use.
Mutually exclusive with the key()
attribute.
CacheConfig.keyGenerator()
public abstract String cacheManager
CacheManager
to use to
create a default CacheResolver
if none
is set already.
Mutually exclusive with the cacheResolver()
attribute.
SimpleCacheResolver
,
CacheConfig.cacheManager()
public abstract String cacheResolver
CacheResolver
to use.CacheConfig.cacheResolver()
public abstract String condition
Default is ""
, meaning the method result is always cached.
The SpEL expression evaluates against a dedicated context that provides the following meta-data:
#root.method
, #root.target
, and #root.caches
for
references to the method
, target object, and
affected cache(s) respectively.#root.methodName
) and target class
(#root.targetClass
) are also available.
#root.args[1]
, #p1
or #a1
. Arguments
can also be accessed by name if that information is available.public abstract String unless
Unlike condition()
, this expression is evaluated after the method
has been called and can therefore refer to the result
.
Default is ""
, meaning that caching is never vetoed.
The SpEL expression evaluates against a dedicated context that provides the following meta-data:
#result
for a reference to the result of the method invocation. For
supported wrappers such as Optional
, #result
refers to the actual
object, not the wrapper#root.method
, #root.target
, and #root.caches
for
references to the method
, target object, and
affected cache(s) respectively.#root.methodName
) and target class
(#root.targetClass
) are also available.
#root.args[1]
, #p1
or #a1
. Arguments
can also be accessed by name if that information is available.public abstract boolean sync
unless()
is not supportedCache.get(Object, Callable)