Caffeine cache 3.1.8 · com.github.benmanes.caffeine.cache.stats.CacheStats

Modifier and Type	Field and Description
private static final CacheStats	EMPTY_STATS
private final long	evictionCount
private final long	evictionWeight
private final long	hitCount
private final long	loadFailureCount
private final long	loadSuccessCount
private final long	missCount
private final long	totalLoadTime

Access	Constructor and Description
private	CacheStats(@NonNegative long hitCount, @NonNegative long missCount, @NonNegative long loadSuccessCount, @NonNegative long loadFailureCount, @NonNegative long totalLoadTime, @NonNegative long evictionCount, @NonNegative long evictionWeight)

Method Summary

Modifier and Type	Method and Description
public @NonNegative double	Returns: the average number of nanoseconds spent loading new values averageLoadPenalty() Returns the average number of nanoseconds spent loading new values.
public static CacheStats	Returns: an empty statistics instance empty() Returns a statistics instance where no cache events have been recorded.
public boolean	equals(@Nullable Object the reference object with which to compare. o) Overrides java.lang.Object.equals. Indicates whether some other object is "equal to" this one.
public @NonNegative long	Returns: the number of times an entry has been evicted evictionCount() Returns the number of times an entry has been evicted.
public @NonNegative long	Returns: the sum of weights of evicted entities evictionWeight() Returns the sum of weights of evicted entries.
public int	hashCode() Overrides java.lang.Object.hashCode. Returns a hash code value for the object.
public @NonNegative long	Returns: the number of times `Cache` lookup methods have returned a cached value hitCount() Returns the number of times `Cache` lookup methods have returned a cached value.
public @NonNegative double	Returns: the ratio of cache requests which were hits hitRate() Returns the ratio of cache requests which were hits.
public @NonNegative long	Returns: the `loadSuccessCount + loadFailureCount` loadCount() Returns the total number of times that `Cache` lookup methods attempted to load new values.
public @NonNegative long	Returns: the number of times `Cache` lookup methods failed to load a new value loadFailureCount() Returns the number of times `Cache` lookup methods failed to load a new value, either because no value was found or an exception was thrown while loading.
public @NonNegative double	Returns: the ratio of cache loading attempts which threw exceptions loadFailureRate() Returns the ratio of cache loading attempts which threw exceptions.
public @NonNegative long	Returns: the number of times `Cache` lookup methods have successfully loaded a new value loadSuccessCount() Returns the number of times `Cache` lookup methods have successfully loaded a new value.
public CacheStats	Returns: the difference between this instance and `other` minus(CacheStats the statistics to subtract with other) Returns a new `CacheStats` representing the difference between this `CacheStats` and `other`.
public @NonNegative long	Returns: the number of times `Cache` lookup methods have returned an uncached (newly loaded) value, or null missCount() Returns the number of times `Cache` lookup methods have returned an uncached (newly loaded) value, or null.
public @NonNegative double	Returns: the ratio of cache requests which were misses missRate() Returns the ratio of cache requests which were misses.
public static CacheStats	Returns: a `CacheStats` representing the specified statistics of(@NonNegative long the number of cache hits hitCount, @NonNegative long the number of cache misses missCount, @NonNegative long the number of successful cache loads loadSuccessCount, @NonNegative long the number of failed cache loads loadFailureCount, @NonNegative long the total load time (success and failure) totalLoadTime, @NonNegative long the number of entries evicted from the cache evictionCount, @NonNegative long the sum of weights of entries evicted from the cache evictionWeight) Returns a `CacheStats` representing the specified statistics.
public CacheStats	Returns: the sum of the statistics plus(CacheStats the statistics to add with other) Returns a new `CacheStats` representing the sum of this `CacheStats` and `other`.
public @NonNegative long	Returns: the `hitCount + missCount` requestCount() Returns the number of times `Cache` lookup methods have returned either a cached or uncached value.
private static long	saturatedAdd(long a, long b) Returns the sum of `a` and `b` unless it would overflow or underflow in which case `Long.MAX_VALUE` or `Long.MIN_VALUE` is returned, respectively.
public String	toString() Overrides java.lang.Object.toString. Returns a string representation of the object.
public @NonNegative long	Returns: the total number of nanoseconds the cache has spent loading new values totalLoadTime() Returns the total number of nanoseconds the cache has spent loading new values.

Inherited from java.lang.Object:: clone finalize getClass notify notifyAll wait wait wait

EMPTY_STATS	back to summary
private static final CacheStats EMPTY_STATS

evictionCount	back to summary
private final long evictionCount

evictionWeight	back to summary
private final long evictionWeight

hitCount	back to summary
private final long hitCount

loadFailureCount	back to summary
private final long loadFailureCount

loadSuccessCount	back to summary
private final long loadSuccessCount

missCount	back to summary
private final long missCount

totalLoadTime	back to summary
private final long totalLoadTime

CacheStats	back to summary
private CacheStats(@NonNegative long hitCount, @NonNegative long missCount, @NonNegative long loadSuccessCount, @NonNegative long loadFailureCount, @NonNegative long totalLoadTime, @NonNegative long evictionCount, @NonNegative long evictionWeight)

Method Detail

averageLoadPenalty back to summary

averageLoadPenalty	back to summary
public @NonNegative double averageLoadPenalty() Returns the average number of nanoseconds spent loading new values. This is defined as `totalLoadTime / (loadSuccessCount + loadFailureCount)`. Note the values of the metrics are undefined in case of overflow (though it is guaranteed not to throw an exception). If you require specific handling, we recommend implementing your own stats collector. Returns:@NonNegative double the average number of nanoseconds spent loading new values

public @NonNegative double averageLoadPenalty()

Returns the average number of nanoseconds spent loading new values. This is defined as totalLoadTime / (loadSuccessCount + loadFailureCount).

Note

the values of the metrics are undefined in case of overflow (though it is guaranteed not to throw an exception). If you require specific handling, we recommend implementing your own stats collector.

Returns:@NonNegative double: the average number of nanoseconds spent loading new values

empty	back to summary
public static CacheStats empty() Returns a statistics instance where no cache events have been recorded. Returns:CacheStats an empty statistics instance

empty

back to summary

public static CacheStats empty()

Returns a statistics instance where no cache events have been recorded.

Returns:CacheStats: an empty statistics instance

equals back to summary

equals	back to summary
public boolean equals(@Nullable Object o) Overrides java.lang.Object.equals. Doc from java.lang.Object.equals. Indicates whether some other object is "equal to" this one. The `equals` method implements an equivalence relation on non-null object references: It is reflexive: for any non-null reference value `x`, `x.equals(x)` should return `true`. It is symmetric: for any non-null reference values `x` and `y`, `x.equals(y)` should return `true` if and only if `y.equals(x)` returns `true`. It is transitive: for any non-null reference values `x`, `y`, and `z`, if `x.equals(y)` returns `true` and `y.equals(z)` returns `true`, then `x.equals(z)` should return `true`. It is consistent: for any non-null reference values `x` and `y`, multiple invocations of `x.equals(y)` consistently return `true` or consistently return `false`, provided no information used in `equals` comparisons on the objects is modified. For any non-null reference value `x`, `x.equals(null)` should return `false`. An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes. Parameters o:@Nullable Object the reference object with which to compare. Returns:boolean `true` if this object is the same as the obj argument; `false` otherwise. Annotations @Override

public boolean equals(@Nullable Object o)

Overrides java.lang.Object.equals.

Doc from java.lang.Object.equals.

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

It is reflexive: for any non-null reference value x, x.equals(x) should return true.
It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
For any non-null reference value x, x.equals(null) should return false.

An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.

Parameters

o:@Nullable Object: the reference object with which to compare.

Returns:boolean

true if this object is the same as the obj argument; false otherwise.

Annotations

@Override

evictionCount	back to summary
public @NonNegative long evictionCount() Returns the number of times an entry has been evicted. This count does not include manual invalidations. Returns:@NonNegative long the number of times an entry has been evicted

evictionCount

back to summary

public @NonNegative long evictionCount()

Returns the number of times an entry has been evicted. This count does not include manual invalidations.

Returns:@NonNegative long: the number of times an entry has been evicted

evictionWeight	back to summary
public @NonNegative long evictionWeight() Returns the sum of weights of evicted entries. This total does not include manual invalidations. Returns:@NonNegative long the sum of weights of evicted entities

evictionWeight

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public @NonNegative long evictionWeight()

Returns the sum of weights of evicted entries. This total does not include manual invalidations.

Returns:@NonNegative long: the sum of weights of evicted entities

hashCode back to summary

hashCode	back to summary
public int hashCode() Overrides java.lang.Object.hashCode. Doc from java.lang.Object.hashCode. Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by `java.util.HashMap`. The general contract of `hashCode` is: Whenever it is invoked on the same object more than once during an execution of a Java application, the `hashCode` method must consistently return the same integer, provided no information used in `equals` comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application. If two objects are equal according to the `equals` method, then calling the `hashCode` method on each of the two objects must produce the same integer result. It is not required that if two objects are unequal according to the `equals` method, then calling the `hashCode` method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables. Returns:int a hash code value for this object. Annotations @Override

public int hashCode()

Overrides java.lang.Object.hashCode.

Doc from java.lang.Object.hashCode.

Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by java.util.HashMap.

The general contract of hashCode is:

Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
If two objects are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result.
It is not required that if two objects are unequal according to the equals method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.

Returns:int

a hash code value for this object.

Annotations

@Override

hitCount back to summary

hitCount	back to summary
public @NonNegative long hitCount() Returns the number of times `Cache` lookup methods have returned a cached value. Returns:@NonNegative long the number of times `Cache` lookup methods have returned a cached value

public @NonNegative long hitCount()

Returns the number of times Cache lookup methods have returned a cached value.

Returns:@NonNegative long: the number of times Cache lookup methods have returned a cached value

hitRate back to summary

hitRate	back to summary
public @NonNegative double hitRate() Returns the ratio of cache requests which were hits. This is defined as `hitCount / requestCount`, or `1.0` when `requestCount == 0`. Note that `hitRate + missRate =~ 1.0`. Returns:@NonNegative double the ratio of cache requests which were hits

public @NonNegative double hitRate()

Returns the ratio of cache requests which were hits. This is defined as hitCount / requestCount, or 1.0 when requestCount == 0. Note that hitRate + missRate =~ 1.0.

Returns:@NonNegative double: the ratio of cache requests which were hits

loadCount back to summary

loadCount	back to summary
public @NonNegative long loadCount() Returns the total number of times that `Cache` lookup methods attempted to load new values. This includes both successful load operations, as well as those that threw exceptions. This is defined as `loadSuccessCount + loadFailureCount`. Note the values of the metrics are undefined in case of overflow (though it is guaranteed not to throw an exception). If you require specific handling, we recommend implementing your own stats collector. Returns:@NonNegative long the `loadSuccessCount + loadFailureCount`

public @NonNegative long loadCount()

Returns the total number of times that Cache lookup methods attempted to load new values. This includes both successful load operations, as well as those that threw exceptions. This is defined as loadSuccessCount + loadFailureCount.

Note

the values of the metrics are undefined in case of overflow (though it is guaranteed not to throw an exception). If you require specific handling, we recommend implementing your own stats collector.

Returns:@NonNegative long: the loadSuccessCount + loadFailureCount

loadFailureCount back to summary

loadFailureCount	back to summary
public @NonNegative long loadFailureCount() Returns the number of times `Cache` lookup methods failed to load a new value, either because no value was found or an exception was thrown while loading. This is always incremented in conjunction with `missCount`, though `missCount` is also incremented when cache loading completes successfully (see `loadSuccessCount`). Multiple concurrent misses for the same key will result in a single load operation. Returns:@NonNegative long the number of times `Cache` lookup methods failed to load a new value

public @NonNegative long loadFailureCount()

Returns the number of times Cache lookup methods failed to load a new value, either because no value was found or an exception was thrown while loading. This is always incremented in conjunction with missCount, though missCount is also incremented when cache loading completes successfully (see loadSuccessCount). Multiple concurrent misses for the same key will result in a single load operation.

Returns:@NonNegative long: the number of times Cache lookup methods failed to load a new value

loadFailureRate back to summary

loadFailureRate	back to summary
public @NonNegative double loadFailureRate() Returns the ratio of cache loading attempts which threw exceptions. This is defined as `loadFailureCount / (loadSuccessCount + loadFailureCount)`, or `0.0` when `loadSuccessCount + loadFailureCount == 0`. Note the values of the metrics are undefined in case of overflow (though it is guaranteed not to throw an exception). If you require specific handling, we recommend implementing your own stats collector. Returns:@NonNegative double the ratio of cache loading attempts which threw exceptions

public @NonNegative double loadFailureRate()

Returns the ratio of cache loading attempts which threw exceptions. This is defined as loadFailureCount / (loadSuccessCount + loadFailureCount), or 0.0 when loadSuccessCount + loadFailureCount == 0.

Note

the values of the metrics are undefined in case of overflow (though it is guaranteed not to throw an exception). If you require specific handling, we recommend implementing your own stats collector.

Returns:@NonNegative double: the ratio of cache loading attempts which threw exceptions

loadSuccessCount back to summary

loadSuccessCount	back to summary
public @NonNegative long loadSuccessCount() Returns the number of times `Cache` lookup methods have successfully loaded a new value. This is always incremented in conjunction with `missCount`, though `missCount` is also incremented when an exception is encountered during cache loading (see `loadFailureCount`). Multiple concurrent misses for the same key will result in a single load operation. Returns:@NonNegative long the number of times `Cache` lookup methods have successfully loaded a new value

public @NonNegative long loadSuccessCount()

Returns the number of times Cache lookup methods have successfully loaded a new value. This is always incremented in conjunction with missCount, though missCount is also incremented when an exception is encountered during cache loading (see loadFailureCount). Multiple concurrent misses for the same key will result in a single load operation.

Returns:@NonNegative long: the number of times Cache lookup methods have successfully loaded a new value

minus	back to summary
public CacheStats minus(CacheStats other) Returns a new `CacheStats` representing the difference between this `CacheStats` and `other`. Negative values, which aren't supported by `CacheStats` will be rounded up to zero. Parameters other:CacheStats the statistics to subtract with Returns:CacheStats the difference between this instance and `other`

missCount back to summary

missCount	back to summary
public @NonNegative long missCount() Returns the number of times `Cache` lookup methods have returned an uncached (newly loaded) value, or null. Multiple concurrent calls to `Cache` lookup methods on an absent value can result in multiple misses, all returning the results of a single cache load operation. Returns:@NonNegative long the number of times `Cache` lookup methods have returned an uncached (newly loaded) value, or null

public @NonNegative long missCount()

Returns the number of times Cache lookup methods have returned an uncached (newly loaded) value, or null. Multiple concurrent calls to Cache lookup methods on an absent value can result in multiple misses, all returning the results of a single cache load operation.

Returns:@NonNegative long: the number of times Cache lookup methods have returned an uncached (newly loaded) value, or null

missRate back to summary

missRate	back to summary
public @NonNegative double missRate() Returns the ratio of cache requests which were misses. This is defined as `missCount / requestCount`, or `0.0` when `requestCount == 0`. Note that `hitRate + missRate =~ 1.0`. Cache misses include all requests which weren't cache hits, including requests which resulted in either successful or failed loading attempts, and requests which waited for other threads to finish loading. It is thus the case that `missCount >= loadSuccessCount + loadFailureCount`. Multiple concurrent misses for the same key will result in a single load operation. Returns:@NonNegative double the ratio of cache requests which were misses

public @NonNegative double missRate()

Returns the ratio of cache requests which were misses. This is defined as missCount / requestCount, or 0.0 when requestCount == 0. Note that hitRate + missRate =~ 1.0. Cache misses include all requests which weren't cache hits, including requests which resulted in either successful or failed loading attempts, and requests which waited for other threads to finish loading. It is thus the case that missCount >= loadSuccessCount + loadFailureCount. Multiple concurrent misses for the same key will result in a single load operation.

Returns:@NonNegative double: the ratio of cache requests which were misses

of back to summary

of	back to summary
public static CacheStats of(@NonNegative long hitCount, @NonNegative long missCount, @NonNegative long loadSuccessCount, @NonNegative long loadFailureCount, @NonNegative long totalLoadTime, @NonNegative long evictionCount, @NonNegative long evictionWeight) Returns a `CacheStats` representing the specified statistics. Parameters hitCount:@NonNegative long the number of cache hits missCount:@NonNegative long the number of cache misses loadSuccessCount:@NonNegative long the number of successful cache loads loadFailureCount:@NonNegative long the number of failed cache loads totalLoadTime:@NonNegative long the total load time (success and failure) evictionCount:@NonNegative long the number of entries evicted from the cache evictionWeight:@NonNegative long the sum of weights of entries evicted from the cache Returns:CacheStats a `CacheStats` representing the specified statistics

public static CacheStats of(@NonNegative long hitCount, @NonNegative long missCount, @NonNegative long loadSuccessCount, @NonNegative long loadFailureCount, @NonNegative long totalLoadTime, @NonNegative long evictionCount, @NonNegative long evictionWeight)

Returns a CacheStats representing the specified statistics.

Parameters

hitCount:@NonNegative long: the number of cache hits
missCount:@NonNegative long: the number of cache misses
loadSuccessCount:@NonNegative long: the number of successful cache loads
loadFailureCount:@NonNegative long: the number of failed cache loads
totalLoadTime:@NonNegative long: the total load time (success and failure)
evictionCount:@NonNegative long: the number of entries evicted from the cache
evictionWeight:@NonNegative long: the sum of weights of entries evicted from the cache

Returns:CacheStats

a CacheStats representing the specified statistics

plus	back to summary
public CacheStats plus(CacheStats other) Returns a new `CacheStats` representing the sum of this `CacheStats` and `other`. Note the values of the metrics are undefined in case of overflow (though it is guaranteed not to throw an exception). If you require specific handling, we recommend implementing your own stats collector. Parameters other:CacheStats the statistics to add with Returns:CacheStats the sum of the statistics

requestCount back to summary

requestCount	back to summary
public @NonNegative long requestCount() Returns the number of times `Cache` lookup methods have returned either a cached or uncached value. This is defined as `hitCount + missCount`. Note the values of the metrics are undefined in case of overflow (though it is guaranteed not to throw an exception). If you require specific handling, we recommend implementing your own stats collector. Returns:@NonNegative long the `hitCount + missCount`

public @NonNegative long requestCount()

Returns the number of times Cache lookup methods have returned either a cached or uncached value. This is defined as hitCount + missCount.

Note

the values of the metrics are undefined in case of overflow (though it is guaranteed not to throw an exception). If you require specific handling, we recommend implementing your own stats collector.

Returns:@NonNegative long: the hitCount + missCount

saturatedAdd back to summary

saturatedAdd	back to summary
private static long saturatedAdd(long a, long b) Returns the sum of `a` and `b` unless it would overflow or underflow in which case `Long.MAX_VALUE` or `Long.MIN_VALUE` is returned, respectively. Annotations @SuppressWarnings:ShortCircuitBoolean

private static long saturatedAdd(long a, long b)

Returns the sum of a and b unless it would overflow or underflow in which case Long.MAX_VALUE or Long.MIN_VALUE is returned, respectively.

Annotations

@SuppressWarnings:ShortCircuitBoolean

toString	back to summary
public String toString() Overrides java.lang.Object.toString. Doc from java.lang.Object.toString. Returns a string representation of the object. Returns:String a string representation of the object. Annotations @Override

toString

back to summary

public String toString()

Overrides java.lang.Object.toString.

Doc from java.lang.Object.toString.

Returns a string representation of the object.

Returns:String

a string representation of the object.

Annotations

@Override

totalLoadTime back to summary

totalLoadTime	back to summary
public @NonNegative long totalLoadTime() Returns the total number of nanoseconds the cache has spent loading new values. This can be used to calculate the miss penalty. This value is increased every time `loadSuccessCount` or `loadFailureCount` is incremented. Returns:@NonNegative long the total number of nanoseconds the cache has spent loading new values

public @NonNegative long totalLoadTime()

Returns the total number of nanoseconds the cache has spent loading new values. This can be used to calculate the miss penalty. This value is increased every time loadSuccessCount or loadFailureCount is incremented.

Returns:@NonNegative long: the total number of nanoseconds the cache has spent loading new values

public final Class CacheStats

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