com.googlecode.concurrentlinkedhashmap
Class ConcurrentLinkedHashMap.Builder<K,V>

java.lang.Object
  com.googlecode.concurrentlinkedhashmap.ConcurrentLinkedHashMap.Builder<K,V>

Enclosing class:

ConcurrentLinkedHashMap<K,V>

public static final class ConcurrentLinkedHashMap.Builder<K,V>
extends Object

A builder that creates ConcurrentLinkedHashMap instances. It provides a flexible approach for constructing customized instances with a named parameter syntax. It can be used in the following manner:

 // a cache of the groups that a user belongs to
   ConcurrentMap<User, Set<Group>> groups = new Builder<User, Set<Group>>()
       .weigher(Weighers.<Group>set())
       .maximumWeightedCapacity(5000)
       .build();
 
 

Constructor Summary

ConcurrentLinkedHashMap.Builder()

Method Summary

ConcurrentLinkedHashMap<K,V>	build() Creates a new ConcurrentLinkedHashMap instance.
ConcurrentLinkedHashMap.Builder<K,V>	capacityLimiter(CapacityLimiter capacityLimiter) Specifies an algorithm to determine if the maximum capacity has been exceeded and that an entry should be evicted from the map.
ConcurrentLinkedHashMap.Builder<K,V>	concurrencyLevel(int concurrencyLevel) Specifies the estimated number of concurrently updating threads.
ConcurrentLinkedHashMap.Builder<K,V>	initialCapacity(int initialCapacity) Specifies the initial capacity of the hash table (default 16).
ConcurrentLinkedHashMap.Builder<K,V>	listener(EvictionListener<K,V> listener) Specifies an optional listener that is registered for notification when an entry is evicted.
ConcurrentLinkedHashMap.Builder<K,V>	maximumWeightedCapacity(int maximumWeightedCapacity) Specifies the maximum weighted capacity to coerces the map to and may exceed it temporarily.
ConcurrentLinkedHashMap.Builder<K,V>	weigher(Weigher<? super V> weigher) Specifies an algorithm to determine how many the units of capacity a value consumes.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ConcurrentLinkedHashMap.Builder

public ConcurrentLinkedHashMap.Builder()

Method Detail

initialCapacity

public ConcurrentLinkedHashMap.Builder<K,V> initialCapacity(int initialCapacity)

Specifies the initial capacity of the hash table (default 16). This is the number of key-value pairs that the hash table can hold before a resize operation is required.

Parameters:

initialCapacity - the initial capacity used to size the hash table to accommodate this many entries.

Throws:

IllegalArgumentException - if the initialCapacity is negative

maximumWeightedCapacity

public ConcurrentLinkedHashMap.Builder<K,V> maximumWeightedCapacity(int maximumWeightedCapacity)

Specifies the maximum weighted capacity to coerces the map to and may exceed it temporarily.

Parameters:

maximumWeightedCapacity - the weighted threshold to bound the map by

Throws:

IllegalArgumentException - if the maximumWeightedCapacity is negative

concurrencyLevel

public ConcurrentLinkedHashMap.Builder<K,V> concurrencyLevel(int concurrencyLevel)

Specifies the estimated number of concurrently updating threads. The implementation performs internal sizing to try to accommodate this many threads (default 16).

Parameters:

concurrencyLevel - the estimated number of concurrently updating threads

Throws:

IllegalArgumentException - if the concurrencyLevel is less than or equal to zero

listener

public ConcurrentLinkedHashMap.Builder<K,V> listener(EvictionListener<K,V> listener)

Specifies an optional listener that is registered for notification when an entry is evicted.

Parameters:

listener - the object to forward evicted entries to

Throws:

NullPointerException - if the listener is null

weigher

public ConcurrentLinkedHashMap.Builder<K,V> weigher(Weigher<? super V> weigher)

Specifies an algorithm to determine how many the units of capacity a value consumes. The default algorithm bounds the map by the number of key-value pairs by giving each entry a weight of 1.

Parameters:

weigher - the algorithm to determine a value's weight

Throws:

NullPointerException - if the weigher is null

capacityLimiter

public ConcurrentLinkedHashMap.Builder<K,V> capacityLimiter(CapacityLimiter capacityLimiter)

Specifies an algorithm to determine if the maximum capacity has been exceeded and that an entry should be evicted from the map. The default algorithm bounds the map by the maximum weighted capacity. The evaluation of whether the map has exceeded its capacity is performed after an insertion or update operation.

Parameters:

capacityLimiter - the algorithm to determine whether to evict an entry

Throws:

NullPointerException - if the capacity limiter is null

build

public ConcurrentLinkedHashMap<K,V> build()

Creates a new ConcurrentLinkedHashMap instance.

Throws:

IllegalStateException - if the maximum weighted capacity was not set