What is the purpose of @Cacheable in Spring?
In Spring, the @Cacheable annotation is used to indicate that Spring will cache the method’s result, allowing the same method to be called again directly from the cache without executing the actual logic of the method.
Specifically, the @Cacheable annotation can be applied at the method level to enable caching functionality. When a method is marked with the @Cacheable annotation, Spring will first check if the result of the method is already in the cache. If it is, the cached result will be returned directly; if not, the method’s actual logic will be executed and the result will be stored in the cache for future calls.
The workflow of the @Cacheable annotation is as follows:
- Spring first checks if there is a cached item matching the method parameters in the cache.
- If a cache item exists, the result from the cache will be returned directly, and the actual logic of the method will not be executed.
- If the cached item does not exist, the actual logic of the method is executed, and the result is stored in the cache for future use.
By using the @Cacheable annotation, the performance of methods can be effectively improved, especially for methods that are computationally expensive and frequently accessed. Additionally, the @Cacheable annotation also provides some other attributes that can be used to customize cache behavior, such as specifying the cache’s name and key.
It is important to note that the @Cacheable annotation will only be executed the first time a method is called. Subsequent calls will directly retrieve the result from the cache. Hence, if the result of the method may change, it is necessary to use the @CacheEvict annotation to clear the cache and ensure the latest result is obtained.
