org.opendaylight.infrautils.caches.baseimpl

Class DelegatingNullSafeBaseCache<K,V>

java.lang.Object

com.google.common.collect.ForwardingObject

org.opendaylight.infrautils.caches.baseimpl.DelegatingNullSafeBaseCache<K,V>

All Implemented Interfaces:

AutoCloseable, BaseCache<K,V>

Direct Known Subclasses:

DelegatingNullSafeCache, DelegatingNullSafeCheckedCache

@Beta
public abstract class DelegatingNullSafeBaseCache<K,V>
extends com.google.common.collect.ForwardingObject
implements BaseCache<K,V>

Constructor Summary

Constructors

Constructor and Description
DelegatingNullSafeBaseCache()

Method Summary

Modifier and Type	Method and Description
Map<K,V>	asMap() Returns a view of the entries stored in this cache as an immutable map.
protected static <K> Iterable<K>	checkNonNullKeys(@Nullable Iterable<K> keys)
protected static <K,V> com.google.common.collect.ImmutableMap<K,V>	checkReturnValue(@Nullable com.google.common.collect.ImmutableMap<K,V> map)
protected static <K,V> V	checkReturnValue(K key, V value)
void	close()
protected abstract BaseCache<K,V>	delegate()
void	evict(K key) Evict an entry from the cache.
CacheManager	getManager()
void	put(K key, V value) Puts a new entry into the Cache, replacing any existing one.

Methods inherited from class com.google.common.collect.ForwardingObject

toString

Methods inherited from class java.lang.Object

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

Constructor Detail

DelegatingNullSafeBaseCache

public DelegatingNullSafeBaseCache()

Method Detail

delegate

protected abstract BaseCache<K,V> delegate()

Specified by:

delegate in class com.google.common.collect.ForwardingObject

evict

public void evict(K key)

Description copied from interface: BaseCache

Evict an entry from the cache. If the cache does not currently contain an entry under this key, then this is ignored. If it does, that entry is evicted, to be re-calculated on the next get.

Use CacheManager.evictAll() to evict all entries of the entire cache.

Specified by:

evict in interface BaseCache<K,V>

put

public void put(K key,
                V value)

Description copied from interface: BaseCache

Puts a new entry into the Cache, replacing any existing one.

Normally, you often never need to call this method, as in regular usage scenarios a cache API client just invokes Cache.get(Object) (or CheckedCache.get(Object), which then internally (may) use the CacheFunction (or CheckedCacheFunction) - without you ever having had to explicitly put something into the Cache.

This method is ONLY (!) intended for "optimizations". It is useful if the code using a cache already has a key and value (e.g. following an external update notification event kind of thing) and wants to "save time" on an expected subsequent Cache.get(Object) (or CheckedCache.get(Object) invoking the CacheFunction (or CheckedCacheFunction) unnecessarily, using this "hint" to "propose" an entry to the cache.

Any code using this must expect key/value pairs that have been put into a cache to disappear at any time (e.g. when the cache is full and this key/value hasn't been used, or after a programmatic or end-user operator initiated eviction), and be able to obtain THE SAME value from the CacheFunction (or CheckedCacheFunction), for the given key.

Failure to implement calls to this put method consistent with the implementation of the cache's get function WILL lead to weird cache inconsistencies!

Some Cache implementations may IGNORE this "hint" method.

Specified by:

put in interface BaseCache<K,V>

Parameters:

key - the key of the proposed new cache entry

value - the value of the proposed new cache entry

asMap

public Map<K,V> asMap()

Description copied from interface: BaseCache

Returns a view of the entries stored in this cache as an immutable map.

Specified by:

asMap in interface BaseCache<K,V>

getManager

public CacheManager getManager()

Specified by:

getManager in interface BaseCache<K,V>

close

public void close()
           throws Exception

Specified by:

close in interface AutoCloseable

Throws:

Exception

checkNonNullKeys

protected static <K> Iterable<K> checkNonNullKeys(@Nullable Iterable<K> keys)

checkReturnValue

protected static <K,V> V checkReturnValue(K key,
                                          V value)

checkReturnValue

protected static <K,V> com.google.common.collect.ImmutableMap<K,V> checkReturnValue(@Nullable com.google.common.collect.ImmutableMap<K,V> map)