Annotation 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 EL 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.
- 从以下版本开始:
- 4.0
- 作者:
- Costin Leau, Phillip Webb, Stephane Nicoll, Sam Brannen
- 另请参阅:
-
可选元素概要
可选元素修饰符和类型可选元素说明The bean name of the customCacheManagerto use to create a defaultCacheResolverif none is set already.String[]Names of the caches in which method invocation results are stored.The bean name of the customCacheResolverto use.Expression Language (SpEL) expression used for making the method caching conditional.Expression Language (SpEL) expression for computing the key dynamically.The bean name of the customKeyGeneratorto use.booleanSynchronize the invocation of the underlying method if several threads are attempting to load a value for the same key.Expression Language (SpEL) expression used to veto method caching.String[]Alias forcacheNames().
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元素详细资料
-
value
Alias forcacheNames().- 默认值:
- {}
-
cacheNames
Names of the caches in which method invocation results are stored.Names may be used to determine the target cache (or caches), matching the qualifier value or bean name of a specific bean definition.
- 从以下版本开始:
- 4.0
- 另请参阅:
- 默认值:
- {}
-
key
String keyExpression Language (SpEL) expression for computing the key dynamically.Default is
"", meaning all method parameters are considered as a key, unless a customkeyGenerator()has been configured.The EL expression evaluates against a dedicated context that provides the following meta-data:
#root.method,#root.target, and#root.cachesfor references to themethod, target object, and affected cache(s) respectively.- Shortcuts for the method name (
#root.methodName) and target class (#root.targetClass) are also available. - Method arguments can be accessed by index. For instance the second argument
can be accessed via
#root.args[1],#p1or#a1. Arguments can also be accessed by name if that information is available.
- 默认值:
- ""
-
keyGenerator
String keyGeneratorThe bean name of the customKeyGeneratorto use.Mutually exclusive with the
key()attribute.- 默认值:
- ""
-
cacheManager
String cacheManagerThe bean name of the customCacheManagerto use to create a defaultCacheResolverif none is set already.Mutually exclusive with the
cacheResolver()attribute.- 默认值:
- ""
-
cacheResolver
String cacheResolverThe bean name of the customCacheResolverto use.- 默认值:
- ""
-
condition
String conditionExpression Language (SpEL) expression used for making the method caching conditional. Cache the result if the condition evaluates totrue.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.cachesfor references to themethod, target object, and affected cache(s) respectively.- Shortcuts for the method name (
#root.methodName) and target class (#root.targetClass) are also available. - Method arguments can be accessed by index. For instance the second argument
can be accessed via
#root.args[1],#p1or#a1. Arguments can also be accessed by name if that information is available.
- 默认值:
- ""
-
unless
String unlessExpression Language (SpEL) expression used to veto method caching. Veto caching the result if the condition evaluates totrue.Unlike
condition(), this expression is evaluated after the method has been called and can therefore refer to theresult.Default is
"", meaning that caching is never vetoed.The EL expression evaluates against a dedicated context that provides the following meta-data:
#resultfor a reference to the result of the method invocation. For supported wrappers such asOptional,#resultrefers to the actual object, not the wrapper#root.method,#root.target, and#root.cachesfor references to themethod, target object, and affected cache(s) respectively.- Shortcuts for the method name (
#root.methodName) and target class (#root.targetClass) are also available. - Method arguments can be accessed by index. For instance the second argument
can be accessed via
#root.args[1],#p1or#a1. Arguments can also be accessed by name if that information is available.
- 从以下版本开始:
- 4.0
- 默认值:
- ""
-
sync
boolean syncSynchronize the invocation of the underlying method if several threads are attempting to load a value for the same key. The synchronization leads to a couple of limitations:unless()is not supported- Only one cache may be specified
- No other cache-related operation can be combined
- 从以下版本开始:
- 4.0
- 另请参阅:
- 默认值:
- false
-