CacheCounter (Atlassian Instrumentation Aggregation

java.lang.Object
- com.atlassian.instrumentation.caches.CacheCounter

All Implemented Interfaces:

CacheInstrument, Instrument, Comparable<Instrument>
```
public class CacheCounter
extends Object
implements CacheInstrument
```
CacheCounter can track cache hits and misses and give out statistics about how the cache is performing

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static interface`	`CacheCounter.Sizer` In order to find out how large a cache is, this callback interface is invoked to give a "guesstimate" about how large the cache is at present.

Field Summary

Fields
Modifier and Type	Field and Description
`protected AtomicLong`	`hits`
`protected AtomicLong`	`misses`
`protected AtomicLong`	`missTime`
`protected String`	`name`
`static CacheCounter.Sizer`	`NOOP_SIZER` A sizer that always returns -1
`protected CacheCounter.Sizer`	`sizer`

Constructor Summary

Constructors
Constructor and Description

CacheCounter(String name)

CacheCounter(String name, CacheCounter.Sizer sizer)

Constructors
Constructor and Description
`CacheCounter(String name)`
`CacheCounter(String name, CacheCounter.Sizer sizer)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`int`	`compareTo(Instrument that)`
`long`	`getCacheSize()`
`double`	`getHitMissRatio()`
`long`	`getHits()`
`long`	`getMisses()`
`long`	`getMissTime()`
`String`	`getName()`
`long`	`getValue()`
`long`	`hit()` Call this to record a hits on the instrumented cache
`long`	`miss()` Call this to record a misses on the instrumented cache
`<T> T`	`miss(Callable<T> missObjectCreation)` Call this to record a misses on the instrumented cache and how long it took to create the object that was missed.
`long`	`miss(long nanosecondsTaken)` Call this to record a misses on the instrumented cache and how long it took to create the object that was missed.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - NOOP_SIZER
```
public static final CacheCounter.Sizer NOOP_SIZER
```
    A sizer that always returns -1
  - name
```
protected final String name
```
  - hits
```
protected final AtomicLong hits
```
  - misses
```
protected final AtomicLong misses
```
  - missTime
```
protected final AtomicLong missTime
```
  - sizer
```
protected final CacheCounter.Sizer sizer
```
- Constructor Detail
  - CacheCounter
```
public CacheCounter(String name)
```
  - CacheCounter
```
public CacheCounter(String name,
                    CacheCounter.Sizer sizer)
```
- Method Detail
  - hit
```
public long hit()
```
    Call this to record a hits on the instrumented cache
    
    Returns:
    
    the number of hits for this instrumented cache
  - miss
```
public long miss()
```
    Call this to record a misses on the instrumented cache
    
    Returns:
    
    the number of misses for this instrumented cache
  - miss
```
public long miss(long nanosecondsTaken)
```
    Call this to record a misses on the instrumented cache and how long it took to create the object that was missed. This allows you to know the true cost in time for cache misses.
    
    Parameters:
    
    nanosecondsTaken - the time in nanoseconds it took to create the missed cache object
    
    Returns:
    
    the number of misses for this instrumented cache
  - miss
```
public <T> T miss(Callable<T> missObjectCreation)
```
    Call this to record a misses on the instrumented cache and how long it took to create the object that was missed. This allows you to know the true cost in time for cache misses.
    This method takes a Callable that allows you to "create" the missed object and auto record the time it took to create the missed object.
    
    Parameters:
    
    missObjectCreation - the callable that creates the missed object
    
    Returns:
    
    the number of misses for this instrumented cache
  - getName
```
public String getName()
```
    Specified by:
    
    getName in interface Instrument
    
    Returns:
    
    the name of the Instrument.
  - getValue
```
public long getValue()
```
    Specified by:
    
    getValue in interface Instrument
    
    Returns:
    
    returns the value of the monitored reading at the time the call was made
  - compareTo
```
public int compareTo(Instrument that)
```
    Specified by:
    
    compareTo in interface Comparable<Instrument>
  - getHits
```
public long getHits()
```
    Specified by:
    
    getHits in interface CacheInstrument
    
    Returns:
    
    the total number of hits that have been made on the underlying instrumented cache
  - getMisses
```
public long getMisses()
```
    Specified by:
    
    getMisses in interface CacheInstrument
    
    Returns:
    
    the total number of misses that have been made on the underlying instrumented cache
  - getMissTime
```
public long getMissTime()
```
    Specified by:
    
    getMissTime in interface CacheInstrument
    
    Returns:
    
    the total time it has take to create objects because of cache misses on the underlying instrumented cache
  - getHitMissRatio
```
public double getHitMissRatio()
```
    Specified by:
    
    getHitMissRatio in interface CacheInstrument
    
    Returns:
    
    the ration of hits divided by the misses on the underlying instrumented cache
  - getCacheSize
```
public long getCacheSize()
```
    Specified by:
    
    getCacheSize in interface CacheInstrument
    
    Returns:
    
    the size of the underlying instrumented cache

Class CacheCounter

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

NOOP_SIZER

name

hits

misses

missTime

sizer

Constructor Detail

CacheCounter

CacheCounter

Method Detail

hit

miss

miss

miss

getName

getValue

compareTo

getHits

getMisses

getMissTime

getHitMissRatio

getCacheSize