Spring 从具有另一个签名的方法中逐出缓存

Question

I cache some queries in one method

    @Override
    @Cacheable(cacheNames = "user-actions")
    public UserAction getUserAction(UUID userId) {
        ...
    }

I'd like to evict cache in another method. It works if method has the same signature, for example

    @CacheEvict(cacheNames = "user-actions")
    public void evictUserLevel(UUID userId) {
        log.info("Cache user-actions has been evicted");
    }

But is there ways to evict cache if I don't pass userId to method in which cache will be evicted, or if it has more than one parameter? This doesn't work:

    @CacheEvict(cacheNames = "user-actions")
    public void processEvent(UserEvent event, UUID userId) {
        ...
    }

Answer 1

This works for me

    @CacheEvict(cacheNames = "user-events", key = "#root.args[1]")
    public void processEvent(UserEvent event, UUID userId) {
        ...
    }

root.args - means method arguments and [1] - is an index of an argument

Answer 2

Quoting from the documentation

Default Key Generation

Since caches are essentially key-value stores, each invocation of a cached method needs to be translated into a suitable key for cache access. Out of the box, the caching abstraction uses a simple KeyGenerator based on the following algorithm:

• If no params are given, return 0.

• If only one param is given, return that instance.

• If more the one param is given, return a key computed from the hashes of all parameters.

---

Hence below signature does not work as key is computed from event and userId .

@CacheEvict(cacheNames = "user-actions")
public void processEvent(UserEvent event, UUID userId) {
   ...
}

---

But is there ways to evict cache if I don't pass userId to method in which cache will be evicted, or if it has more than one parameter?

For no parameter

set allEntries=true , which will clear all entries.

@CacheEvict(cacheNames = "user-actions", allEntries = true)
public void evictAll() {
}

For more than one parameter

specify the parameter for the key , refer to Custom Key Generation Declaration for details.

@CacheEvict(cacheNames = "user-actions", key = "#userId")
public void processEvent(UserEvent event, UUID userId) {
...
}