Target Cache gets checked twice for every cache hit [SPR-11592] #16216
Description
Jacques Stadler opened SPR-11592 and commented
Problem
Whenever you execute a cached method that has already been executed once, and therefore its result can be fetched from the cache, there will be 2 cache hits that happen for one execution of this method.
See e.g. this snippet from the referenced GitHub project:
ServiceToCache obj = (ServiceToCache) context.getBean("serviceToCache");
Cache cache = (Cache) context.getBean("cache");
String key = "1";
String result1 = obj.returnSomeString(key);
// Before it calls the method the cache is checked
verify(cache, times(1)).get(key);
String result2 = obj.returnSomeString(key);
// Here we would expect that the cache was only called twice, but it is being called 3 times.
verify(cache, times(3)).get(key);I would expect that if I execute a cached method once, there should only be one cache hit, not two.
Solution
As I see it the problem lies in org.springframework.cache.interceptor.CacheAspectSupport.execute(Invoker, CacheOperationContexts):
// Collect puts from any @Cachable miss
List<CachePutRequest> cachePutRequests = new ArrayList<CachePutRequest>();
// NOTE: This produces the first cache hit
collectPutRequests(contexts.get(CacheableOperation.class), ExpressionEvaluator.NO_RESULT, cachePutRequests, true);
ValueWrapper result = null;
// We only attempt to get a cached result if there are no put requests
if (cachePutRequests.isEmpty() && contexts.get(CachePutOperation.class).isEmpty()) {
// NOTE: This produces the second cache hit
result = findCachedResult(contexts.get(CacheableOperation.class));
}I suppose the cached value should be fetched once, before calling the two methods (collectPutRequests, findCachedResult) above.
Affects: 4.0.2
Reference URL: https://github.com/stadler/poc-spring-cache
Issue Links:
- Spring caching: combining multiple @Cacheable within @Caching annotation doesn't work [SPR-11124] #15750 Spring caching: combining multiple
@Cacheablewithin@Cachingannotation doesn't work
0 votes, 5 watchers