```
public interface CacheStatistics
```
Set of metrics for cache statistics. The cache statistics can be retrieved via CacheControl.sampleStatistics(). The statistics may be unavailable if disabled via Cache2kBuilder.disableStatistics(boolean). General information about the cache is available via CacheInfo.
For exporting to a monitoring system the modules cache2k-jmx and cache2k-micrometer are available.
Statistics are retrieved with minimum effect on the running application and avoid locks. This may lead to slight inconsistencies within the metrics, e.g. the two values getTotalLoadMillis() and getLoadCount() are not updated atomically.

Author:

Jens Wilke

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`long`	`getClearCallsCount()`	Number of `Cache.clear()` invocations.
`long`	`getClearedCount()`	Number entries removed from the cache by the `Cache.clear()` operation.
`long`	`getEvictedCount()`	An entry was evicted from the cache because of size limits.
`long`	`getEvictedOrRemovedWeight()`	Accumulated number of weight evicted or removed entries
`long`	`getExpiredCount()`	A cache entry has expired.
`long`	`getGetCount()`	How often data was requested from the cache.
`double`	`getHitRate()`	The percentage of cache accesses the cache delivered data.
`long`	`getInsertCount()`	How many times a new entry was inserted into the cache.
`long`	`getKeyMutationCount()`	Number of key mutations occurred.
`long`	`getLoadCount()`	How many times a load succeeded.
`long`	`getLoadExceptionCount()`	Number of exceptions thrown by the `CacheLoader`.
`double`	`getMillisPerLoad()`	Average number of milliseconds per load.
`long`	`getMissCount()`	Counter of the event that: a client requested a data which was not present in the cache or had expired.
`long`	`getPutCount()`	The total number of insert or update operations.
`long`	`getRefreshCount()`	Refreshed entries counter.
`long`	`getRefreshedHitCount()`	How many times there was a hit on a refreshed entry.
`long`	`getRefreshFailedCount()`	Counter how many times a refresh failed, e.g.
`long`	`getRemoveCount()`	Number of remove operations.
`long`	`getSuppressedLoadExceptionCount()`	Number of exceptions thrown by the `CacheLoader` that were ignored and the previous data value got returned.
`long`	`getTotalLoadMillis()`	Total number of time spent loading entries from the cache loader.

- Method Detail
  - getInsertCount
```
long getInsertCount()
```
    How many times a new entry was inserted into the cache.
  - getGetCount
```
long getGetCount()
```
    How often data was requested from the cache.
  - getMissCount
```
long getMissCount()
```
    Counter of the event that: a client requested a data which was not present in the cache or had expired. In other word containsKey does not count a miss.
  - getLoadCount
```
long getLoadCount()
```
    How many times a load succeeded.
  - getLoadExceptionCount
```
long getLoadExceptionCount()
```
    Number of exceptions thrown by the CacheLoader.
  - getSuppressedLoadExceptionCount
```
long getSuppressedLoadExceptionCount()
```
    Number of exceptions thrown by the CacheLoader that were ignored and the previous data value got returned.
  - getMillisPerLoad
```
double getMillisPerLoad()
```
    Average number of milliseconds per load.
  - getTotalLoadMillis
```
long getTotalLoadMillis()
```
    Total number of time spent loading entries from the cache loader.
  - getRefreshCount
```
long getRefreshCount()
```
    Refreshed entries counter.
  - getRefreshFailedCount
```
long getRefreshFailedCount()
```
    Counter how many times a refresh failed, e.g. because there were not enough thread resources available.
  - getRefreshedHitCount
```
long getRefreshedHitCount()
```
    How many times there was a hit on a refreshed entry. This counter is incremented once, after a refreshed entry is requested by the application for the first time. That means the quotient from refreshedCount and refreshedHitCount is the efficiency of refreshing.
  - getExpiredCount
```
long getExpiredCount()
```
    A cache entry has expired. The counter is incremented after the actual expiry.
    This can mean that the cache entry is removed or just marked as expired in case that the keep value option is enabled.
    
    See Also:
    
    Cache2kConfig.setKeepDataAfterExpired(boolean)
  - getEvictedCount
```
long getEvictedCount()
```
    An entry was evicted from the cache because of size limits.
  - getEvictedOrRemovedWeight
```
long getEvictedOrRemovedWeight()
```
    Accumulated number of weight evicted or removed entries
  - getPutCount
```
long getPutCount()
```
    The total number of insert or update operations.
  - getRemoveCount
```
long getRemoveCount()
```
    Number of remove operations.
  - getClearedCount
```
long getClearedCount()
```
    Number entries removed from the cache by the Cache.clear() operation.
  - getClearCallsCount
```
long getClearCallsCount()
```
    Number of Cache.clear() invocations.
  - getKeyMutationCount
```
long getKeyMutationCount()
```
    Number of key mutations occurred. This should be always 0, otherwise it is an indicator that the key object was modified after it was stored in the cache. Whenever `keyMutationCount` is non-zero, check and correct your application.
    How it works: When an entry is evicted the cache checks whether the hashCode of the key object is identical to the code when it was inserted. If not, the counter is incremented. When a mutation is detected, also a warning is logged but only once during the cache lifetime.
  - getHitRate
```
double getHitRate()
```
    The percentage of cache accesses the cache delivered data.

Interface CacheStatistics

Method Summary

Method Detail

getInsertCount

getGetCount

getMissCount

getLoadCount

getLoadExceptionCount

getSuppressedLoadExceptionCount

getMillisPerLoad

getTotalLoadMillis

getRefreshCount

getRefreshFailedCount

getRefreshedHitCount

getExpiredCount

getEvictedCount

getEvictedOrRemovedWeight

getPutCount

getRemoveCount

getClearedCount

getClearCallsCount

getKeyMutationCount

getHitRate