Module org.apache.jena.base

Package org.apache.jena.atlas.lib.cache

Class CacheSimple<K,V>

java.lang.Object

org.apache.jena.atlas.lib.cache.CacheSimple<K,V>

All Implemented Interfaces:

Cache<K,V>

public class CacheSimple<K,V>
extends Object
implements Cache<K,V>

A simple fixed size cache that uses the hash code to address a slot. The clash policy is to overwrite.

The cache has very low overhead - there is no object creation during lookup or insert.

This cache is not thread safe.

Constructor Summary

Constructors

Constructor	Description
CacheSimple(int size)
CacheSimple(int size, BiConsumer<K,V> dropHandler)

Method Summary

Modifier and Type	Method	Description
void	clear()
boolean	containsKey(K key)	Does the cache contain the key?
V	get(K key, Function<K,V> function)	Get from cache; if not present, call the Function to fill the cache slot.
V	getIfPresent(K key)	Get from cache - or return null.
V	getOrFill(K key, Callable<V> callable)	Get from cache; if not present, call the Callable to try to fill the cache.
static <K, V> V	getOrFillNoSync(Cache<K,V> cache, K key, Callable<V> callable)	Implementation of getOrFill based on Cache.get and Cache.put This function is not thread safe.
static <K, V> V	getOrFillNoSync(Cache<K,V> cache, K key, Function<K,V> function)	Implementation of getOrFill based on Cache.get and Cache.put This function is not thread safe.
boolean	isEmpty()
Iterator<K>	keys()	Iterate over all keys.
void	put(K key, V thing)	Insert into the cache
void	remove(K key)	Remove from cache - return true if key referenced an entry
long	size()	Current size of cache

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.jena.atlas.lib.Cache

stats

Constructor Details

CacheSimple

public CacheSimple(int size)

CacheSimple

public CacheSimple(int size,
 BiConsumer<K,V> dropHandler)

Method Details

clear

public void clear()

Specified by:

clear in interface Cache<K,V>

containsKey

public boolean containsKey(K key)

Description copied from interface: Cache

Does the cache contain the key?

Specified by:

containsKey in interface Cache<K,V>

getIfPresent

public V getIfPresent(K key)

Description copied from interface: Cache

Get from cache - or return null.

Specified by:

getIfPresent in interface Cache<K,V>

getOrFill

public V getOrFill(K key,
 Callable<V> callable)

Description copied from interface: Cache

Get from cache; if not present, call the Callable to try to fill the cache. This operation should be atomic.

Specified by:

getOrFill in interface Cache<K,V>

get

public V get(K key,
 Function<K,V> function)

Description copied from interface: Cache

Get from cache; if not present, call the Function to fill the cache slot. This operation should be atomic.

Specified by:

get in interface Cache<K,V>

getOrFillNoSync

public static <K,
V> V getOrFillNoSync(Cache<K,V> cache,
 K key,
 Function<K,V> function)

Implementation of getOrFill based on Cache.get and Cache.put This function is not thread safe.

getOrFillNoSync

public static <K,
V> V getOrFillNoSync(Cache<K,V> cache,
 K key,
 Callable<V> callable)

Implementation of getOrFill based on Cache.get and Cache.put This function is not thread safe.

put

public void put(K key,
 V thing)

Description copied from interface: Cache

Insert into the cache

Specified by:

put in interface Cache<K,V>

remove

public void remove(K key)

Description copied from interface: Cache

Remove from cache - return true if key referenced an entry

Specified by:

remove in interface Cache<K,V>

size

public long size()

Description copied from interface: Cache

Current size of cache

Specified by:

size in interface Cache<K,V>

keys

public Iterator<K> keys()

Description copied from interface: Cache

Iterate over all keys. Iterating over the keys requires the caller be thread-safe.

Specified by:

keys in interface Cache<K,V>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Cache<K,V>