Spring 3.1 Cache Abstraction: How do I switch the KeyGenerator?

[tobias79]

Hello everybody,

I have a String as a key in my cache. Since the DefaultKeyGenerator uses hashCode() for generating the key I cannot use it, because there may be collisions.

It's no problem to provide another implementation of KeyGenerator, but I'm missing a simple way to use it. There is no such attribute on <cache:annotation-driven/> nor on CacheManager nor on Cache, just on the Aspect itself, but I don't wanna declare it myself.

Can somebody help me?

Tobias

[tobias79]

Okay, still don't know how to switch the default KeyGenerator implementation, but I realized that I don't really need it when I use the key attribute on the @Cacheable annotation.

By the way, there is an error in the reference documentation. You need to reference the parameter with a hash: key="#parametername", otherwise Spel is trying to find a property parametername on some helper class.

[ajainy]

Another problem with Default implementation, it's calculating hashCode of method param, but doesn't include methodName in calculations.
I remember reading documentation, hashCode is combination of methodName + params.

[ascasso]

I've ran into the same problem of not having the method name used in the hashCode computation.

I can't figure out how to specify my own implementation of org.springframework.cache.KeyGenerator, the documentation mentions it should be possible.

[harshi]

Have you figured it out? I ran into the same issue? There is setter method in CacheAspectSupport for injecting customKeygenerator but there is no way how to configure it.


Regards
Harshi

[AuPanner]

Old thread, but here is how you do it:

<cache:annotation-driven key-generator="myKeyGenerator" />
<bean id="myKeyGenerator" class="com.whereever.spring.MyLessSuckyKeyGenerato r" />

As for the DefaultKeyGenerator, you can bypass it with:

@Cacheable(value="myCache",key="#root.methodName,# parameter,...")