public class SingleFileStore<K,V> extends Object implements AdvancedLoadWriteStore<K,V>
AdvancedLoadWriteStore
. This file store
stores cache values in a single file <location>/<cache name>.dat,
keys and file positions are kept in memory.
Note: this CacheStore implementation keeps keys and file positions in memory!
The current implementation needs about 100 bytes per cache entry, plus the
memory for the key objects.
So, the space taken by this cache store is both the space in the file
itself plus the in-memory index with the keys and their file positions.
With this in mind and to avoid the cache store leading to
OutOfMemoryExceptions, you can optionally configure the maximum number
of entries to maintain in this cache store, which affects both the size
of the file and the size of the in-memory index. However, setting this
maximum limit results in older entries in the cache store to be eliminated,
and hence, it only makes sense configuring a maximum limit if Infinispan
is used as a cache where loss of data in the cache store does not lead to
data loss, and data can be recomputed or re-queried from the original data
source.
This class is fully thread safe, yet allows for concurrent load / store
of individual cache entries.AdvancedCacheWriter.PurgeListener<K>
Modifier and Type | Field and Description |
---|---|
protected InitializationContext |
ctx |
static int |
KEY_POS_11_0 |
static int |
KEY_POS_BEFORE_11 |
static byte[] |
MAGIC_11_0 |
static byte[] |
MAGIC_BEFORE_11 |
Constructor and Description |
---|
SingleFileStore() |
Modifier and Type | Method and Description |
---|---|
void |
clear()
Removes all the data from the storage.
|
boolean |
contains(Object key)
The base class implementation calls
CacheLoader.loadEntry(Object) for this, we can do better because
we keep all keys in memory. |
boolean |
delete(Object key) |
void |
destroy()
Method to be used to destroy and clean up any resources associated with this store.
|
io.reactivex.rxjava3.core.Flowable<MarshallableEntry<K,V>> |
entryPublisher(Predicate<? super K> filter,
boolean fetchValue,
boolean fetchMetadata)
Publishes all entries from this store.
|
SingleFileStoreConfiguration |
getConfiguration() |
static File |
getStoreFile(GlobalConfiguration globalConfiguration,
String locationPath,
String cacheName) |
void |
init(InitializationContext ctx)
Used to initialize a cache loader.
|
boolean |
isAvailable() |
MarshallableEntry<K,V> |
loadEntry(Object key)
Fetches an entry from the storage.
|
io.reactivex.rxjava3.core.Flowable<K> |
publishKeys(Predicate<? super K> filter)
Publishes all the keys from this store.
|
void |
purge(Executor threadPool,
AdvancedCacheWriter.PurgeListener task)
Using the thread in the pool, removed all the expired data from the persistence storage.
|
int |
size()
Returns the number of elements in the store.
|
void |
start()
Invoked on component start
|
void |
stop()
Invoked on component stop
|
void |
write(MarshallableEntry<? extends K,? extends V> marshalledEntry)
Persists the entry to the storage.
|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
bulkUpdate, deleteBatch
public static final byte[] MAGIC_BEFORE_11
public static final byte[] MAGIC_11_0
public static final int KEY_POS_BEFORE_11
public static final int KEY_POS_11_0
protected InitializationContext ctx
public static File getStoreFile(GlobalConfiguration globalConfiguration, String locationPath, String cacheName)
public void init(InitializationContext ctx)
CacheLoader
PersistenceManager
when setting up cache loaders.init
in interface CacheLoader<K,V>
init
in interface CacheWriter<K,V>
public void start()
Lifecycle
public void stop()
Lifecycle
public void destroy()
ExternalStore
This method will ensure the store is stopped and properly cleans up all resources for it.
destroy
in interface ExternalStore<K,V>
public boolean isAvailable()
isAvailable
in interface CacheLoader<K,V>
isAvailable
in interface CacheWriter<K,V>
isAvailable
in interface ExternalStore<K,V>
public boolean contains(Object key)
CacheLoader.loadEntry(Object)
for this, we can do better because
we keep all keys in memory.contains
in interface CacheLoader<K,V>
public void write(MarshallableEntry<? extends K,? extends V> marshalledEntry)
CacheWriter
write
in interface CacheWriter<K,V>
MarshallableEntry
public void clear()
AdvancedCacheWriter
clear
in interface AdvancedCacheWriter<K,V>
public boolean delete(Object key)
delete
in interface CacheWriter<K,V>
public MarshallableEntry<K,V> loadEntry(Object key)
CacheLoader
MarshallableEntry
needs to be created here, InitializationContext.getMarshallableEntryFactory()
()} and InitializationContext.getByteBufferFactory()
should be used.loadEntry
in interface CacheLoader<K,V>
public io.reactivex.rxjava3.core.Flowable<K> publishKeys(Predicate<? super K> filter)
AdvancedCacheLoader
Subscriber
s as desired. Keys are not retrieved until a given Subscriber requests
them from the Subscription
.
Stores will return only non expired keys
publishKeys
in interface AdvancedCacheLoader<K,V>
filter
- a filter - null is treated as allowing all entriespublic io.reactivex.rxjava3.core.Flowable<MarshallableEntry<K,V>> entryPublisher(Predicate<? super K> filter, boolean fetchValue, boolean fetchMetadata)
AdvancedCacheLoader
Subscriber
s as desired. Entries are not retrieved until a given Subscriber requests
them from the Subscription
.
If fetchMetadata is true this store must guarantee to not return any expired entries.
entryPublisher
in interface AdvancedCacheLoader<K,V>
filter
- a filter - null is treated as allowing all entriesfetchValue
- whether or not to fetch the value from the persistent store. E.g. if the iteration is
intended only over the key set, no point fetching the values from the persistent store as
wellfetchMetadata
- whether or not to fetch the metadata from the persistent store. E.g. if the iteration is
intended only ove the key set, then no point fetching the metadata from the persistent store
as wellpublic void purge(Executor threadPool, AdvancedCacheWriter.PurgeListener task)
AdvancedCacheWriter
When this method returns all entries will be purged and no tasks will be running due to this loader in the provided executor. If however an exception is thrown there could be tasks still pending or running in the executor.
purge
in interface AdvancedCacheWriter<K,V>
public int size()
AdvancedCacheLoader
size
in interface AdvancedCacheLoader<K,V>
public SingleFileStoreConfiguration getConfiguration()
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