com.sitewhere.spi.cache

Interface ICache<K,V>

Type Parameters:

K -

V -

public interface ICache<K,V>

Interface for a cache that stores objects by id.

Method Summary

Modifier and Type	Method and Description
void	addListener(ICacheListener<V> listener) Add a listener for changes to the cache.
void	clear() Clear all elements from cache.
V	get(K key) Get value based on a given key.
int	getElementCount() Get count of elements currently in cache.
long	getHitCount() Get the number of cache hits.
long	getRequestCount() Get the number of requests made to the cache.
CacheType	getType() Get the cache type.
void	put(K key, V value) Add or replace value for the given key.
void	remove(K key) Remove an element from the cache.

Method Detail

getType

CacheType getType()

Get the cache type.

Returns:

the type of cache

get

V get(K key)
throws SiteWhereException

Get value based on a given key.

Parameters:

key - unique key

Returns:

corresponding value or null if not found

Throws:

SiteWhereException - if implementation can not get value

put

void put(K key,
         V value)
  throws SiteWhereException

Add or replace value for the given key.

Parameters:

key - unique key

value - new or replacement value

Throws:

SiteWhereException - if implementation can not put value

remove

void remove(K key)
     throws SiteWhereException

Remove an element from the cache.

Parameters:

key - unique key for object to remove

Throws:

SiteWhereException - if implementation can not remove value

addListener

void addListener(ICacheListener<V> listener)
          throws SiteWhereException

Add a listener for changes to the cache.

Parameters:

listener -

Throws:

SiteWhereException

clear

void clear()
    throws SiteWhereException

Clear all elements from cache.

Throws:

SiteWhereException - if implementation can not clear cache

getElementCount

int getElementCount()
             throws SiteWhereException

Get count of elements currently in cache.

Returns:

count of cache elements

Throws:

SiteWhereException - if implementation can not get count

getRequestCount

long getRequestCount()
              throws SiteWhereException

Get the number of requests made to the cache.

Returns:

count of requests made to cache

Throws:

SiteWhereException - if implementation can not get count

getHitCount

long getHitCount()
          throws SiteWhereException

Get the number of cache hits.

Returns:

count of cache hits

Throws:

SiteWhereException - if implementation can not count hits