LruCache (Resin 4.0.s170329)

java.lang.Object
- com.caucho.util.LruCache<K,V>

```
public final class LruCache<K,V>
extends java.lang.Object
```
Fixed length cache with a LRU replacement policy. If cache items implement CacheListener, they will be informed when they're removed from the cache.
Null keys are not allowed. LruCache is synchronized.

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static interface LruCache.Entry<K,V>
Interface for entry iterator;

Nested Classes
Modifier and Type	Class and Description
`static interface`	`LruCache.Entry<K,V>` Interface for entry iterator;

Constructor Summary

Constructors
Constructor and Description
`LruCache(int initialCapacity)` Create the LRU cache with a specific capacity.
`LruCache(int initialCapacity, boolean isStatistics)` Create the LRU cache with a specific capacity.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`clear()` Clears the cache
`boolean`	`compareAndPut(V testValue, K key, V value)` Puts a new item in the cache if the current value matches oldValue.
`V`	`get(K key)` Get an item from the cache and make it most recently used.
`int`	`getCapacity()` Returns the LRU cache capacity
`long`	`getHitCount()` Returns the hit count.
`long`	`getMissCount()` Returns the miss count.
`java.util.Iterator<LruCache.Entry<K,V>>`	`iterator()` Returns the entries
`java.util.Iterator<K>`	`keys()` Returns the keys stored in the cache
`java.util.Iterator<K>`	`keys(java.util.Iterator<K> oldIter)` Returns keys stored in the cache using an old iterator
`V`	`put(K key, V value)` Puts a new item in the cache.
`V`	`putIfNew(K key, V value)` Puts a new item in the cache.
`V`	`remove(K key)` Removes an item from the cache
`boolean`	`removeLongestTail()` Remove the last item in the LRU.
`boolean`	`removeTail()` Remove the last item in the LRU
`void`	`setEnableListeners(boolean isEnable)` Disable the listeners
`void`	`setEnableStatistics(boolean isEnable)`
`int`	`size()` Returns the current number of entries in the cache.
`java.util.Iterator<V>`	`values()` Returns the values in the cache
`java.util.Iterator<V>`	`values(java.util.Iterator<V> oldIter)`

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

- Constructor Detail
  - LruCache
```
public LruCache(int initialCapacity)
```
    Create the LRU cache with a specific capacity.
    
    Parameters:
    
    initialCapacity - minimum capacity of the cache
  - LruCache
```
public LruCache(int initialCapacity,
                boolean isStatistics)
```
    Create the LRU cache with a specific capacity.
    
    Parameters:
    
    initialCapacity - minimum capacity of the cache
- Method Detail
  - setEnableListeners
```
public void setEnableListeners(boolean isEnable)
```
    Disable the listeners
  - setEnableStatistics
```
public void setEnableStatistics(boolean isEnable)
```
  - size
```
public int size()
```
    Returns the current number of entries in the cache.
  - getCapacity
```
public int getCapacity()
```
    Returns the LRU cache capacity
  - clear
```
public void clear()
```
    Clears the cache
  - get
```
public V get(K key)
```
    Get an item from the cache and make it most recently used.
    
    Parameters:
    
    key - key to lookup the item
    
    Returns:
    
    the matching object in the cache
  - put
```
public V put(K key,
             V value)
```
    Puts a new item in the cache. If the cache is full, remove the LRU item.
    
    Parameters:
    
    key - key to store data
    
    value - value to be stored
    
    Returns:
    
    old value stored under the key
  - putIfNew
```
public V putIfNew(K key,
                  V value)
```
    Puts a new item in the cache. If the cache is full, remove the LRU item.
    
    Parameters:
    
    key - key to store data
    
    value - value to be stored
    
    Returns:
    
    the value actually stored
  - compareAndPut
```
public boolean compareAndPut(V testValue,
                             K key,
                             V value)
```
    Puts a new item in the cache if the current value matches oldValue.
    
    Parameters:
    
    key - the key
    
    value - the new value
    
    testValue - the value to test against the current
    
    Returns:
    
    true if the put succeeds
  - removeTail
```
public boolean removeTail()
```
    Remove the last item in the LRU
  - removeLongestTail
```
public boolean removeLongestTail()
```
    Remove the last item in the LRU. In this case, remove from the list with the longest length. For functions like Cache disk space, this is a better solution than the struct LRU removal.
  - remove
```
public V remove(K key)
```
    Removes an item from the cache
    
    Parameters:
    
    key - the key to remove
    
    Returns:
    
    the value removed
  - keys
```
public java.util.Iterator<K> keys()
```
    Returns the keys stored in the cache
  - keys
```
public java.util.Iterator<K> keys(java.util.Iterator<K> oldIter)
```
    Returns keys stored in the cache using an old iterator
  - values
```
public java.util.Iterator<V> values()
```
    Returns the values in the cache
  - values
```
public java.util.Iterator<V> values(java.util.Iterator<V> oldIter)
```
  - iterator
```
public java.util.Iterator<LruCache.Entry<K,V>> iterator()
```
    Returns the entries
  - getHitCount
```
public long getHitCount()
```
    Returns the hit count.
  - getMissCount
```
public long getMissCount()
```
    Returns the miss count.

Class LruCache<K,V>

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

LruCache

LruCache

Method Detail

setEnableListeners

setEnableStatistics

size

getCapacity

clear

get

put

putIfNew

compareAndPut

removeTail

removeLongestTail

remove

keys

keys

values

values

iterator

getHitCount

getMissCount